Patent ID: 6932318
Filing Date: 2005-08-23
Classification: F16K

Abstract:
1. A flow control device comprising: an inlet port through which fluid is supplied; an outlet port through which the fluid is delivered; a valve body which is arranged in a passage between the inlet port and the outlet port so as to open and close the passage; a valve body guide means which moves said valve body so as to allow the fluid in said passage to flow at a flow rate which is lower than a basic control rate of said flow control device, said valve body guide means pushing down and pulling up said valve body; and a fine controller which controls a range of movement of said valve body, wherein said valve body guide means comprises a piston which is movable relative to said valve body along an axis of the valve body, said fine controller controls a range of movement of said piston, and a pressure control diaphragm which drives said valve body by a pressure of compressed air which acts on one face of said pressure control diaphragm and which is driven by said piston.