Patent ID: 9632511
Date: 2017-04-25
CPC Classifications: F16K,G01F,G05D,Y10T

Claim:
1. A pressure type flow control system with flow monitoring, comprising: (a) an inlet side passage for fluid; (b) a control valve and a valve drive unit of a pressure type flow control unit that is connected to a downstream side of the inlet side passage; (c) a thermal type flow sensor that is connected to a downstream side of the control valve; (d) an orifice that is installed on a first fluid passage communicatively connected to a downstream side of the thermal type flow sensor; (e) a temperature sensor that is provided near the first fluid passage between the control valve and the orifice to measure temperature of fluid in the first fluid passage; (f) a pressure sensor that is provided for the first fluid passage between the control valve and the orifice to measure pressure of fluid in the first fluid passage; (g) an outlet side passage that is communicatively connected to the orifice; and (h) a first control unit comprising wherein, when a difference between the first flow rate of the fluid computed by the flow sensor control unit and the second flow rate of the fluid computed by the pressure type flow rate arithmetic and control unit exceeds a set value, then the first control unit performs an alarm indication; wherein the control valve is a nearest control valve to the orifice on an upstream side, and there are no other control valves between the control valve and the orifice.