Patent ID: 6889706

Claim:
A flow rate control apparatus comprising: a pulsation-attenuating means for balancing a regulated pilot pressure from a pressure-regulating section and a primary pressure of a pressure fluid introduced into said flow rate control apparatus and flowing through a fluid passage to attenuate pressure fluctuation caused by pulsation of said pressure fluid; and a flow rate control mechanism having a valve plug for opening/closing said fluid passage, said flow rate control mechanism controlling a flow amount of said pressure fluid flowing through said fluid passage by adjusting a valve lift amount of said valve plug with a linear actuator controlled based on a control signal from a control unit. wherein said pulsation-attenuating means includes a pressure-regulating section for regulating a pressure fluid introduced from a pressure fluid supply port to have a predetermined pressure, and a pulsation-balancing section provided with a valve member for opening/closing said fluid passage based on said pressure fluid from said pressure-regulating section, and wherein said valve member includes a sliding plate arranged displaceably between a first diaphragm and a second diaphragm, a valve plug connected to said sliding plate, a seal member attached to an outer surface of said sliding plate, and an intermediate member provided between said sliding plate and said valve plug.