| 摘要 |
PURPOSE:To make it possible to control the flow rate over the broad range, by providing a orifice for measuring a large flow rate and an orifice for measuring a small flow rate, measuring the flow rate by changing the orifice in response to the flow rate, thereby controlling flow rate. CONSTITUTION:The flow rate of gas is measured by the orifice 3g for measuring the large from rate and the orifice 4g for measuring the small flow rate. The measured result is outputted from a flow rate oscillator 13g and inputted to an operating device 9. The operating device outputs the operated result, and a regulating valve 8g is controlled. When the amount of the gas is reduced owing to an accident and the like, a first cut off valve 7g is closed by the output of the operating device, and flow rate is measured by only the orifice 4g for measuring the small flow rate. The flow rate is controlled by regulating the regulating valve 8g. In this way, the flow rate is controlled from the large flow rate to the small flow rate. |
