| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a gas analysis apparatus capable of keeping a pressure in a gas cell constant even if external (atmospheric) pressure nearby a gas introduction pipe intake and a gas discharge pipe outlet varies. <P>SOLUTION: A gas analysis apparatus includes: a gas cell 1; a gas introduction pipe 2 and a gas discharge pipe 3 connected to the gas cell; a first pump 4 provided to the gas introduction pipe; a branch pipe 5 connected to the gas introduction pipe downstream from the first pump; a first back pressure valve 7 provided to the branch pipe; a second pump 8 provided to the gas discharge pipe; a second back pressure valve 9 provided to the gas discharge pipe upstream from the second pump; and a detection unit which detects concentration of a specific gas component included in a sample gas flowing in the gas cell. The first back pressure valve operates so that a pressure in the gas introduction pipe downstream from a branch point is held at a gas cell upstream-side pressure set value, and the second back pressure valve operates so that a pressure in the gas cell or an upstream-side pressure of the second back pressure valve in the gas discharge pipe is held at an in-gas-cell pressure set value. <P>COPYRIGHT: (C)2013,JPO&INPIT |
