Flow control and monitoring system

Claim 1

A fluid control system comprising: A. a fluid conduit adapted to have a pressurized fluid supplied at the inlet thereto; B. means in said conduit intermediate the inlet and outlet thereof to restrict fluid flow therethrough; C. first control means in said conduit upstream of said restriction means to compensate for changes in pressure of the sUpply fluid and to vary the flow of fluid in accordance therewith to maintain a desired mass flow rate constant at the outlet of said conduit; D. means responsive to the pressure differential across said restriction means and for sensing the deviation in the mass flow rate therethrough from a desired valve; E. second control means for regulating said first control means to compensate for said deviation in mass flow rate across said restriction means sensed by said differential pressure responsive means; with said first control means including F. valve means in said conduit intermediate said restriction means to control the mass flow rate of fluid through said conduit, and G. pressure responsive means controlling the flow position of said valve means with said pressure responsive means having one side responsive to the pressure of the outlet side of said valve means; said second control means having H. means to apply an output fluid pressure to the other side of said pressure responsive means of said first control means, and I. means to regulate said output fluid pressure as required in accordance with the desired mass flow rate at the outlet of said conduit.