| 摘要 |
PROBLEM TO BE SOLVED: To provide an infrared gas analysis device which can perform analysis with high accuracy.SOLUTION: A humidity adjustment unit 8 for adjusting a water vapor concentration in a gas is provided in a supply path 4 for supplying a reference gas and a sample gas into a sample cell. A bypass flow passage 9 is branched from the supply path 4 at a branching portion 41 provided upstream from the humidity adjustment unit 8 in the supply path 4, and is joined to the supply path 4 at a joining portion 42 provided upstream from the humidity adjustment unit 8 in the supply path 4. The flow passage of the gas is switched to the humidity adjustment unit 8 side or the bypass flow passage 9 side using a solenoid valve SV5 provided in the branching portion 41. In a section from the branching portion 41 to the joining portion 42, a total volume on the humidity adjustment unit 8 side including the volume of the humidity adjustment unit 8 and a total volume on the bypass flow passage 9 side are made approximately the same. The times needed for replacing the gas inside the sample cell at calibration time and at sample measurement time are approximately the same, it is therefore possible to prevent an error in the concentration values measured at calibration time and at sample measurement time, so that analysis can be performed with high accuracy.SELECTED DRAWING: Figure 2 |
