| 摘要 |
The present invention provides a pressure-type flow rate control device that, in fluid flow rate control using a pressure-type flow rate control device, makes it possible to greatly shorten step-down response time during flow rate switching, thereby increasing step-down response characteristics. The present invention is a pressure-type flow rate control device, comprising: a main body provided with a fluid passage connecting a fluid inlet and a fluid outlet and an exhaust gas passage connecting the fluid passage, and an exhaust gas outlet; a control valve for pressure control that is secured on the fluid inlet-side of the main body and opens and closes the upstream side of the fluid passage; a pressure sensor that detects the internal pressure of the fluid passage on the downstream side of the control valve; an orifice provided within the fluid passage downstream from a branching site of the exhaust gas passage; and a control valve for exhaust gas control that opens and closes the exhaust gas passage. When the flow rate of the fluid is changed by the pressure-type flow rate control device, the control valve for pressure control and the control valve for exhaust gas control are activated, the interior of the fluid passage between the control valve for pressure control and the orifice is forcibly vented, thereby increasing the step-down response speed at the time of flow rate change. |
