| 摘要 |
PURPOSE:To make a mixing rate of gas stable by comparing an observed value measured by a gas mixing device with a set value, and controlling the quantity of gas to be mixed with the liquid to a fixed value basing on the compared result. CONSTITUTION:A set value Xa' and a proportional zone Xc of gas mixing rate are inputted in a storage section 33. A gas mixing rate Xa is operated in an operating section 32 of a controlling device 31 by operating a circulating cylinder 8, and the set value Xa' and the proportional zone Xc stored in the storage section 33 are compared with the observed value Xa in a comparing and instructing section 34. If Xa'-Xa is >=Xc, a gas solenoid valve 18 is turned on, and the gas is mixed into the liquid passage 2 by means of the gas mixing device. If Xa'-Xa<Xc, the gas is mixed only during the proportional time into the liquid passage. Further, the liquid is circulated in the liquid passage 2 by driving the circulating cylinder 8. |
