| 摘要 |
PURPOSE: A flow rate controller is provided to automatically and accurately detect the blockage of an orifice with the minimum installation of attachment, thereby preventing abnormal control of flow rate. CONSTITUTION: A flow rate controller comprises a differential flowmeter(20), a flow rate adjusting valve(30), and a controller(40). The differential flowmeter includes an orifice which is installed between a pair of pressure sensors installed in the straight part of a flow pipe, and measures the flow rate by changing the pressure difference obtained from two measurement pressures of the pressure sensors into flow rate. The flow rate adjusting valve is installed in the flow pipe, and the opening degree is controlled so that the difference between the measurement flow rate of the differential flowmeter and the preset flow rate falls within a predetermined range. The controller receives the measurement pressures of the pressure sensors and controls the opening degree of the flow rate adjusting valve. |
