Method and apparatus for determining the physical properties of the gas in the measuring gas chamber

摘要

PROBLEM TO BE SOLVED: To provide a method whose measurement flow is easier than that in a conventionally known method, and a device whose sensor structure is extremely simplified.;SOLUTION: In this method of determining a physical characteristic of gas in a measurement gas chamber, a sensor element having at least one pump cell is used. A first electrode of this pump cell is exposed to the gas in the measurement gas chamber, a second electrode is arranged in a cavity separated from the measurement gas chamber and sealed air-tightly. At time t₀, pump voltage U_p is applied to the pump cell to operate the pump, and pump current flowing through this pump cell is measured. Here, it is determined whether variation characteristic occurs in Nernst counter voltage generated between the first electrode and second electrode occurs. When variation characteristic of Nernst counter voltage is identified, the physical characteristic of the gas is estimated after time t₀ based on the time Δt when this characteristic variation occurs.;COPYRIGHT: (C)2009,JPO&INPIT