Fluid blending systems and control means therefor

Claim 1

A SYSTEM FOR BLENDING TWO DIFFERENT FLUIDS IN PREDETERMINED PROPORTION, COMPRISING: A FIRST PIPE FOR CONDUCTING A FIRST FLUID, AND HAVING A PRESSURE SENSING POINT THEREIN; A SECOND PIPE FOR CONDUCTING A SECOND FLUID DIFFERENT FROM SAID FIRST FLUID, SAID SECOND PIPE BEING CONNECTED TO SAID FIRST PIPE DOWNSTREAM OF SAID SENSING POINT IN SAID FIRST PIPE FOR BLENDING SAID SECOND FLUID WITH SAID FIRST FLUID; A MAIN VALVE CONNECTED IN SAID SECOND PIPE UPSTREAM OF THE POINT OF CONNECTION OF SAID SECOND PIPE WITH SAID FIRST PIPE, AND INCLUDING FLUID PRESSURE ACTUATED MEANS FOR CONTROLLING THE RATE OF FLOW OF SAID SECOND FLUID THROUGH SAID SECOND PIPE IN PREDETERMINED PROPORTION TO THE RATE OF FLOW OF SAID FIRST FLUID IN SAID FIRST PIPE, SAID SECOND PIPE HAVING A PRESSURE SENSING POINT THEREIN BETWEEN SAID MAIN VALVE AND THE POINT OF CONNECTION OF SAID SECOND PIPE WITH SAID FIRST PIPE; AND PILOT VALVE MEANS SEPARATE FROM SAID MAIN VALVE FOR CONTROLLING SAID MAIN VALVE, SAID PILOT VALVE MEANS HAVING A PRESSURE CHAMBER AND HAVING MEANS TO CONNECT SAID PRESSURE CHAMBER WITH THE INLET SIDE OF SAID MAIN VALVE TO DERIVE OPERATING FLUID THEREFROM FOR SAID MAIN VALVE, AND INCLUDING: CONDUIT MEANS CONNECTING SAID PILOT VALVE MEANS WITH SAID FLUID PRESSURE ACTUATED MEANS FOR SUPPLYING OPERATING FLUID TO AND EXHAUSTING OPERATING FLUID FROM SAID FLUID PRESSURE ACTUATED MEANS; A DIFFERENTIAL PRESSURE RESPONSIVE DEVICE, INCLUDING MEANS IN SAID PRESSURE CHAMBER OPERABLE TO SELECTIVELY EITHER ESTABLISH COMMUNICATION BETWEEN SAID PRESSURE CHAMBER AND SAID CONDUIT MEANS TO EXCLUSIVELY SUPPLY SAID OPERATING FLUID TO SAID FLUID PRESSURE ACTUATED MEANS, OR TO COOPERATE WITH SAID CONDUIT MEANS TO EXCLUSIVELY EXHAUST OPERATING FLUID FROM SAID FLUID PRESSURE ACTUATED MEANS THROUGH SAID CONDUIT MEANS; AND MEANS CONNECTED TO SAID SENSING POINTS AND TO SAID DIFFERENTIAL PRESSURE RESPONSIVE DEVICE, AND ARRANGED TO OPERATE SAID DEVICE IN ACCORDANCE WITH THE DIFFERENTIAL OF PRESSURE BETWEEN SAID SENSING POINT, WHEREBY TO CONTROL SAID MAIN VALVE TO VARY THE AMOUNT OF SAID SECOND FLUID FLOWING THROUGH SAID SECOND PIPE IN ACORDANCE WITH CHANGES IN THE RATE OF FLOW OF SAID FIRST FLUID THROUGH SAID FIRST PIPE AND CONSEQUENT CHANGES IN SAID DIFFERENTIAL PRESSURE.

Claim 2

A SYSTEM FOR BLENDING TWO DIFFERENT FLUIDS IN PREDETERMINED PROPORTION, COMPRISING: A FIRST PIPE FOR CONDUCTING A FIRST FLUID, AND HAVING A PRESSURE SENSING POINT THEREIN; A SECOND PIPE FOR CONDUCTING A SECOND FLUID DIFFERENT FROM SAID FIRST FLUID, SAID SECOND PIPE BEING CONNECTED TO SAID FIRST PIPE DOWNSTREAM OF SAID SENSING POINT IN SAID FIRST PIPE FOR BLENDING SAID SECOND FLUID WITH SAID FIRST FLUID; A MAIN VALVE CONNECTED IN SAID SECOND PIPE UPSTREAM OF THE POINT OF CONNECTION OF SAID SECOND PIPE WITH SAID FIRST PIPE, AND INCLUDING FLUID PRESSURE ACTUATED MEANS FOR CONTROLLING THE RATE OF FLOW OF SAID SECOND FLUID THROUGH SAID SECOND PIPE IN PREDETERMINED PROPORTION TO THE RATE OF FLOW OF SAID FIRST FLUID IN SAID FIRST PIPE, SAID SECOND PIPE HAVING A PRESSURE SENSING POINT THEREIN BETWEEN SAID MAIN VALVE AND THE POINT OF CONNECTION OF SAID SECOND PIPE WITH SAID FIRST PIPE; AND PILOT VALVE MEANS SEPARATE FROM SAID MAIN VALVE FOR CONTROLLING SAID MAIN VALVE, SAID PILOT VALVE MEANS HAVING A PRESSURE CHAMBER AND HAVING MEANS TO CONNECT SAID PRESSURE CHAMBER WITH THE INLET SIDE OF SAID MAIN VALVE TO DERIVE OPERATING FLUID THEREFROM FOR SAID MAIN VALVE, AND INCLUDING: CONDUIT MEANS CONNECTING SAID PILOT VALVE MEANS WITH SAID FLUID PRESSURE ACTUATED MEANS FOR SUPPLYING OPERATING FLUID TO AND EXHAUSTING OPERATING FLUID FROM SAID FLUID PRESSURE ACTUATED MEANS; A DIFFERENTIAL PRESSURE RESPONSIVE DEVICE, INCLUDING MEANS IN SAID PRESSURE CHAMBER OPERABLE TO SELECTIVELY EITHER ESTABLISH COMMUNICATION BETWEEN SAID PRESSURE CHAMBER AND SAID CONDUIT MEANS TO EXCLUSIVELY SUPPLY SAID OPERATING FLUID TO SAID FLUID PRESSURE ACTUATED MEANS, OR TO COOPERATE WITH SAID CONDUIT MEANS TO EXCLUSIVELY EXHAUST OPERATING FLUID FROM SAID FLUID PRESSURE ACTUATED MEANS THROUGH SAID CONDUIT MEANS; AND MEANS CONNECTED TO SAID SENSING POINTS AND TO SAID DIFFERENTIAL PRESSURE RESPONSIVE DEVICE, AND ARRANGED TO OPERATE SAID DEVICE IN ACCORDANCE WITH THE DIFFERENTIAL OF PRESSURE BETWEEN SAID SENSING POINT, WHEREBY TO CONTROL SAID MAIN VALVE TO VARY THE AMOUNT OF SAID SECOND FLUID FLOWING THROUGH SAID SECOND PIPE IN ACORDANCE WITH CHANGES IN THE RATE OF FLOW OF SAID FIRST FLUID THROUGH SAID FIRST PIPE AND CONSEQUENT CHANGES IN SAID DIFFERENTIAL PRESSURE.