FLOW CONTROL VALVE

A flow control valve of the present invention includes a housing with an inflow passage and an outflow passage; a body received inside the housing; a cover blocking the opened end of the body to from a pressure chamber; a diaphragm installed inside the pressure chamber; a control passage connecting the pressure chamber and the flow passages; and a servo regulator controlling the opening degree of the control passage. The present invention is characterized in that the diaphragm is divided into an upper diaphragm and a lower diaphragm. In addition, the present invention is characterized in that the servo regulator applies pressure to a space between the upper and lower diaphragms to open and close the inflow passage. Accordingly, the present invention is capable of being applied to various flow control system due to the structure proper to a flow control system requiring a large flow amount; using a large or small solenoid valve by being improved to solve a problem of an existing diaphragm; reducing manufacture cost by simplifying components to reduce a volume of the product; and facilitating the maintenance of the product. Furthermore, the present invention is capable of preventing a loss due to a pressure difference (pressure hunting) generated in the middle of the operation of the flow control valve and regularly maintaining the pressure of an outlet to obtain desirable flow control efficiency.