Apparatus for controlling the operation of multiple combustion zones

Claim 1

APPARATUS COMPRISING MEANS FORMING AT LEAST TWO COMBUSTION ZONES, A BURNER FOR EACH COMBUSTION ZONE, MEANS FOR CONTROLLING FLOW OF COMBUSTION COMPONENT AIR TO SAID BURNER, MEANS FOR CONTROLLING FLOW OF COMBUSTION COMPONENT FUEL TO SAID BURNERS, MEANS FOR CONTROLLING THE RATE OF FLOW OF ONE OF SAID COMBUSTION COMPONENTS, A FLUE GAS ANALYZER, MEANS FOR SELECTIVELY DELIVERING SAMPLES OF FLUE GASES TO SAID ANALYZER FROM EACH OF SAID COMBUSTION ZONES HAVING AN OPERATING BURNER, MEANS FOR OBTAINING A VOLTAGE PROPORTIONAL TO A PRE-SELECTED COMPONENT OF SAID FLUE GAS, SAID COMPONENT VARYING WITH THE RATIO OF FUEL AND AIR FLOW, MEANS FOR OBTAINING A VOLTAGE PROPORTIONAL TO A PRESET DESIRED PERCENTAGE OF SAID PRE-SELECTED COMPONENT IN SAID FLUE GAS, MEANS FOR CONNECTING SAID VOLTAGES IN OPPOSITION TO ONE ANOTHER SO AS TO OBTAIN A VOLTAGE DIFFERENCE, MEANS FOR OBTAINING A VOLTAGE PROPORTIONAL TO THE FLOW OF ONE OF SAID COMBUSTION COMPONENTS TO SAID OPERATING BURNER, MEANS FOR MULTIPLYING SAID LAST NAMED VOLTAGE AND SAID VOLTAGE DIFFERENCE TO OBTAIN A FIRST SIGNAL, MEANS FOR OBTAINING A VOLTAGE PROPORTIONAL TO THE FLOW OF THE OTHER OF SAID COMBUSTION COMPONENTS TO SAID OPERATING BURNER TO OBTAIN A SECOND SIGNAL, MEANS FOR COMPARING SAID SIGNALS, MEANS OPERABLE BY SAID COMPARING MEANS FOR CHANGING THE RATIO BETWEEN FUEL AND AIR FLOW TO BRING THE PRESELECTED COMPONENT OF SAID FLUE GAS TO THE DESIRED PERCENTAGE, MEANS FOR OBTAINING A VOLTAGE PROPORTIONAL TO THE FLOW OF THE SAID OTHER OF SAID COMBUSTION COMPONENTS TO A BURNER IN A SECOND COMBUSTION ZONE TO OBTAIN A THIRD SIGNAL, AND MEANS FOR DISCONNECTING THE COMPARING MEANS FROM SAID SECOND SIGNAL AND PREVENTING RESETTING THEREOF AND CONNECTING THE COMPARING MEANS TO SAID THIRD SIGNAL WHEN THE FLUE GAS DELIVERING MEANS IS ACTUATED TO DELIVER FLUE GAS FROM SAID SECOND COMBUSTION ZONE TO SAID ANALYZER.