Spark ignition system for gas burners with ignition indicator

Claim 1

IN AN AUTOMATIC IGNITION GAS BURNER SYSTEM COMPRISING A GAS BURNER; A SOURCE OF SUPPLY OF GAS FOR SAID BURNER; A NORMALLY CLOSED GAS VALVE SUPPLIED WITH GAS FROM SAID SOURCE AND HAVING A CONTROL ELEMENT RESPONSIVE TO ELECTRICAL CURRENT TO OPEN SAID VALVE AND SUPPLY GAS TO SAID BURNER; A RECHARGEABLE BATTERY; A CONTROL SWITCH; A FIRST THERMALY RESPONSIVE DOUBLE-THROW SWITCH POSITIONED ADJACENT SAID BURNER SO AS TO BE HEATED BY FLAME FROM SAID BURNER WHEN SAID BURNER IS IGNITED, SAID FIRST THERMALLY RESPONSIVE SWITCH BEING CLOSED TO ITS FIRST POSITION IN THE ABSENCE OF FLAME FROM SAID BURNER AND RESPONSIVE TO FLAME FROM SAID BURNER TO CHANGE FROM ITS FIRST POSITION TO ITS SECOND POSITION; ELECTRONIC SWITCH MEANS HAVING A CONTROL ELECTRODE RESPONSIVE TO CHANGES IN VOLTAGE APPLIED THERETO TO TURN SAID ELECTRONIC SWITCH MEANS ON AND OFF; A RESISTANCE-CAPACITANCE TIMING CIRCUIT CONNECTED TO SAID CONTROL ELECTRODE FOR PERMITTING SAID ELECTRONIC SWITCH MEANS TO TURN ON UPON INITIAL FLOW OF CURRENT THROUGH SAID SWITCH MEANS AND THEN AUTOMATICALLY TO TURN OFF AN INTERVAL THE DURATION OF WHICH IS DETERMINED BY THE VALUE OF RESISTANCE IN SAID TIMING CIRCUIT; CIRCUIT MEANS CONNECTING SAID CONTROL SWITCH, SAID THERMALLY RESPONSIVE DOUBLETHROW SWITCH, SAID ELECTRONIC SWITCH MEANS, SAID BATTERY AND SAID VALVE CONTROL ELEMENT IN COMMON SERIES CIRCUIT WITH EACH OTHER SO THAT CLOSING OF SAID CONTROL SWITCH IN THE ABSENCE OF FLAME FROM SAID BURNER CAUSES CURRENT INITIALLY TO PASS THROUGH SAID SERIES CIRCUIT TO OPEN SAID VALVE AND SUPPLY GAS TO SAID BURNER AND, AFTER SAID INTERVAL, TO INTERRUPT SAID CURRENT THEREBY TO PERMIT SAID VALVE TO RETURN TO ITS NORMAL CLOSED STATE IF SAID FLAME IS STILL ABENT FROM SAID BURNER; GAS IGNITER MEANS FOR SAID BURNER; MEANS FOR OPERATING SAID IGNITER MEANS WHEN SAID GAS IS SUPPLIED TO SAID BURNER; A THERMO-ELECTRIC CURRENT GENERATOR POSITIONED TO BE HEATED BY FLAME FROM SID BURNER AND CONNECTED IN COMMON SERIES CIRCUIT WITH SAID CONTROL SWITCH, WITH SAID FIRST THERMALLY RESPONSIVE SWITCH AND WITH SAID VALVE CONTROL ELEMENT SO THAT WHEN SIAD CONTROL SWITCH IS IN CLOSED, WHEN SAID FIRST THERMALLY RESPONSIVE SWITCH IS IN SAID SECOND POSITION THEREOF, AND WHEN SAID THERMO-ELECTRIC CURRENT GENERATOR HAS BEEN SUFFICIENTLY HEATED BY SAID FLAME, SAID GENERATOR SUPPLIES CURRENT TO SAID VALVE CONTROL ELEMENT TO HOLD SAID VALVE OPEN SO LONG AS SAID FLAME PERSISTS, SAID THERMO-ELECTRIC GENERATOR RESPONDING TO HEATING BY SAID FLAME TO DEVELOP A CURRENT THROUGH SAID VALVE CONTROL ELEMENT WHICH IS SUFFICIENT TO HOLD SAID VALVE OPEN BEFORE SAID FIRST THERMALLY RESPONSIVE SWITCH CHANGES FROM SAID FIRST POSITION TO SAID SECOND POSITION THEREOF: THE COMBINATION THEREWITH OF TEMPERATURE-SENSITIVE RESISTANCE MEANS CONNECTED IN SAID TIMING CIRCUIT TO CONTROL SAID DURATION OF SAID INTERVAL FOR WHICH SAID ELECTRONIC SWITCH MEANS IS ON, SAID TEMPERATURESENSITIVE RESISTANCE MEANS BEING POSITIONED TO BE HEATED BY FLAME FROM SAID BURNER AND HAVING A TEMPERATURE CHARACTERISTIC SUCH AS TO RESPOND QUICKLY TO SAID HEATING TO INCREASE THE DURATION OF SAID INTERVAL FOR WHICH SAID ELECTRONIC SWITCH MEANS IS ON BEYOND THE TIME REQUIRED FOR SAID FIRST THERMALLY RESPONSIVE SWITCH TO OPERATE IN RESPONSE TO HEATING BY SAID FLAME.