Gas burner control device

Claim 1

IN A TEMPERATURE MODULATED GAS BURNER ADAPTED TO BE OPERATED AT EQUIVALENT HEAT OUTPUT RATES AT PREDETERMINED TEMPERATURES WITH FUELS OF DIFFERENT CALORIFIC VALUE BY THE MERE INTERCHANGE OF ORIFICE MEMBERS; MEANS FORMING A FUEL CONDUIT LEADING AND DISCHARGING INTO THE BURNER INLET, A METERING ORIFICE THREADEDLY ENGAGED IN FIXED POSITION IN THE END OF SAID CONDUIT, SAID ORIFICE MEMBER HAVING A CYLINDRICAL ORIFICE BORE THERETHROUGH AND BEING FLARED AT ITS UPSTREAM END TO FORM A TAPERED APPROACH THERETO, A SLIDABLY MOUNTED METERING PIN HAVING A CONICALLY POINTED END ARRANGED TO ENTER SAID CYLINDRICAL ORIFICE BORE AT ITS FLARED END, SAID METERING PIN BEING OF LARGER DIAMETER THAN SAID CYLINDRICAL ORIFICE BORE AND ITS CONICALLY POINTED END BEING OF SUBSTANTIALLY THE SAME ANGLE OF TAPER AS SAID FLARED END OF SAID ORIFICE BORE, WHEREBY SAID CONICAL END OF SAID METERING PIN SEATS IN SAID FLARED ORIFICE APPROACH AS IT IS MOVED INWARD AND IS THEREBY STOPPED AT A PREDETERMINED POINT WITH RESPECT TO SAID ORIFICE MEMBER AND SAID CONDUIT IRRESPECTIVE OF THE DIAMETER OF SAID CYLINDRICAL ORIFICE BORE, SAID METERING PIN BEING FURTHER PROVIDED WITH AT LEAST ONE AXIALLY EXTENDING DEPRESSION OF THE ARCUATE SURFACE OF ITS CONICAL END EXTENDING INWARDLY FROM THE POINT TO AT LEAST THE BASE OF ITS CONICAL END TO PROVIDE A PREDETERMINED MINIMUM FLOW WHEN SAID METERING PIN IS SEATED AND TO VARY THE FLOW IN PREDETERMINED RELATIONSHIP WITH AXIAL MOVEMENT OF SAID PIN, A TEMPERATURE RESPONSIVE DEVICE MOUNTED IN FIXED RELATIONSHIP WITH SAID CONDUIT AND SAID ORIFICE MEMBER AND BEING OPERATIVELY CONNECTED TO SAID METERING PIN, AND STOP MEANS LIMITING THE AXIAL MOVEMENT OF SAID METERING PIN TO A RANGE WHEREIN SAID PIN REMAINS ENTERED INTO THE CYLINDRICAL PORTION OF SAID ORIFICE BORE.