Flame supervisory system

Claim 1

IN A MONITORING SYSTEM, A PLURALITY OF FUNCTIONAL DEVICES TO BE MONITORED, MEANS CONTROLLED BY OPERATION OF SAID DEVICES PROVIDING A D.C. SIGNALLING POTENTIAL ONLY SO LONG AS SAID DEVICE ARE OPERATING IN A PREDETERMINED REQUIRED MANNER; A MONITORING CAPACITOR FOR EACH SAID DEVICE AND CONNECTED THEREWITH TO BE CHARGED BY THE CORRESPONDING SAID SIGNALLING POTENTIAL; SCANNING SWITCH MEANS INCLUDING A MONITORING CONTACT CONNECTED WITH EACH SAID MONITORING CAPACITOR AND A SCANNING CONTACTOR MOVABLE IN SCANNING CYCLES AND OPERABLE TO ENGAGE EACH MONITORING CONTACT IN SUCCESSION IN EACH SAID CYCLE TO COMPLETE A MOMENTARY TEST CIRCUIT WITH EACH SAID CAPACITOR FOR THE PURPOSE OF TESTING EACH APPERTAINING FUNCTIONAL DEVICE DURING EACH SUCH SCANNING CYCLE; A SUPERVISORY ELECTRON CONTROL DEVICE HAVING FIRST AND SECOND OPERATING CONDITIONS AND ADAPTED TO BE ACTUATED FROM ONE SAID CONDITION TO THE OTHER BY MEANS OF TRIGGERING POTENTIAL OF PREDETERMINED MINIMUM VALUE APPLIED THERETO FROM ANY OF SAID MONITORING CAPACITORS; CIRCUIT MEANS CONNECTING SAID SCANNING SWITCH MEANS WITH SAID SUPERVISORY CONTROL DEVICE TO APPLY IN SUCCESSION THERETO THE EXISTING CHARGE ON EACH SAID MONITORING CAPACITOR BY SCANNING OPERATION THEREOF WHEREBY TO ACTUATE THE SUPERVISORY CONTROL DEVICE IN RAPID SEQUENCE FROM THE FIRST CONDITION TO THE SECOND CONDITION; MEANS ACTUATED BY THE SUPERVISORY CONTROL DEVICE IN THE SECOND CONDITION THEREOF FOR AUTOMATICALLY RESTORING THE SWITCH TO SAID FIRST CONDITION; AN ELECTRICALLY-CONTROLLED MASTER SWITCH MEANS CONNECTED WITH SAID SUPERVISORY CONTROL DEVICE TO BE ACTUATED BY THE LATTER IN A PARTICULAR CONDITION PROVIDED SAID SUPERVISORY CONTROL DEVICE IS OPERATED IN ITS SAID FIRST CONDITION, AND TO BE OPERATED IN A DIFFERENT CONDITION PROVIDED THE SUPERVISORY CONTROL DEVICE IS OPERATED IN ITS SECOND OPERATIVE CONDITION; AND A HOLDING CIRCUIT MEANS CONNECTING WITH SAID MASTER SWITCH MEANS AND OPERATIVE TO MAINTAIN THE LATTER IN SAID PARTICULAR OPERATIVE CONDITION FOR A PREDETERMINED MINIMUM TIME NOTWITHSTANDING FAILURE OF OPERATION OF THE SUPERVISORY CONTROL DEVICE IN THE SECOND OF ITS OPERATIVE CONDITIONS DURING SAID MINIMUM TIME, WHEREBY THE CHANGE OF OPERATIVE CONDITION OF THE SUPERVISORY CONTROL DEVICE FROM FIRST TO SECOND CONDTION MUST PERSIST FOR THE TIME BEFORE THE MASTER SWITCH MEANS WILL CHANGE FROM ITS SAID PARTICULAR TO ITS DIFFERENT OPERATIVE CONDITION.