| 摘要 |
PROBLEM TO BE SOLVED: To prevent the interference in NO sensitivity of the concentration change of oxygen and improve the measuring precision by guiding a gas to be measured to an internal void space under a prescribed diffusion resistance through a diffusion control part, and regulating the oxygen concentration by an electrochemical pump cell. SOLUTION: A gas to be measured is guided into an internal void space 20 under a prescribed diffusion resistance through a diffusion control part, and regulated to a prescribed oxygen concentration by the pumping action of an electrochemical pump cell 20. The gas regulated in oxygen concentration is guided into an internal void space 22, and finely regulated to a prescribed oxygen concentration by an electrochemical pump cell 44. Further, it is guided to an internal void space 24 through a diffusion control part 18, the component having coupled oxygen in the gas is reduced or diffused by an electrochemical pump cell 58, and an electromotive force corresponding to the oxygen partial pressure regulated by the oxygen generated at that time is generated. This electromotive force is detected by a voltage detecting means Ip to determine a specified component (NOx) in the gas to be measured. |
