Supervisory flame control

Claim 1

IN A FLAME SUPERVISORY SYTEM FOR A PLURALITY OF BURNERS, AND EACH INCLUDING ELECTRICAL FLAME-SENSING MEANS RESPECTIVELY OPERABLE TO ACTUATE A SENSING RELAY RESPONSIVE TO THE PRESENCE OR ABSENCE OF A FLAME AT ONE APPERTAINING BURNER, IMPROVEMENTS COMPRISING, NAMELY: INDICATING MEANS OPERABLY CONTROLLED BY SAID SENSING RELAY TO SEARCH OUT AND INDICATE WHICH BURNER FLAME HAS FAILED, SAID INDICATING MEANS INCLUDING A PLURALITY OF INDICATING LAMPS, EACH DESIGNATING A CORRESPONDING BURNER, AN ELECTROMAGNETICALLY DRIVEN, RAPID-ACTING STEPPING MECHANISM CONNECTED IN A STEPPING CIRCUIT WITH A SET OF NORMALLY CLOSED CONTACTS ON A MASTER RELAY WHICH AR ADAPTED TO BE OPENED ON ENERGIZATION OF SAID SENSING RELAY, SUCH THAT STEPPING OCCURS WHEN SAID MASTER RELAY IS NON-ENERGIZED, AND DOES NOT OCCUR WHEN SAID MASTER RELAY IS ENERGIZED; A BLANK OF SEARCH STEP CONTACTS AND A ROTARY SEARCH WIPER COOPERABLE THEREWITH AND ACTUATED BY SAID STEPPING MECHANISM, SAID WIPER BEING CONNECTED IN SAID STEPPING CIRCUIT TO CONNECT POWER THERETO THROUGH ANY OF SAID SEARCH CONTACTS CONNECTED TO POWER; CONTACT MEANS ON EACH SAID SENSING RELAY EACH CONNECTED TO ONE OF SAID SEARCH CONTACTS AND TO A SOURCE OF POWER AND OPERABLE IN A FIRST PREDETERMINED OPERATIVE CONDITION OF SUCH SENSING RELAY TO CONNECT STEPPING POWER TO THE APERTAINING SEARCH STEP CONTACTS; CHAIN CONTACT MEANS CONNECTED IN A SERIES CIRCUIT WITH SAID MASTER RELAY AND OPERABLE BY EACH SENSING RELAY IN A SECOND OPERATIVE CONDITION THEREOF TO CLOSE AN ENERGIZING CIRCUIT FOR THE MASTER RELAY WHEREBY TO HOLD THE LATTER IN ACTUATED CONDITION SO LONG AS ALL SENSING RELAYS ARE OPERATED IN THE SECOND-NAMED CONDITION AND TO DROP OUT THE MASTER RELAY WHEN ANY ONE OF SAID SENSING RELAYS IS IN SAID PREDETERMINED FIRST CONDITION, SUCH THAT STEPPING ACTION AS AFORESAID WILL BEGIN, AND WILL CONTINUE, SO LONG AS SAID SEARCH AND STEPPING WIPER ENGAGES ANY SEARCH CONTACT WITH POWER CONNECTED THERETO BY SENSING RELAY AND WILL STOP AT THE FIRST SEARCH-STEP CONTACT HAVING NO POWER THUS CONNECTED THERETO; A BANK OF LAMP CONTACTS AND A LAMP WIPER COOPERABLE THEREWITH AND DRIVEN BY SAID STEPPING MECHANISM IN STEP WITH SAID SEARCH WIPER AND CONNECTED IN CIRCUIT WITH SAID LAMPS AND LAMP CONTACTS TO ILLUMINATE ONE OF EACH OF THE SME AT EACH POSITION CORRESPONDING TO ONE OF SAID SEARCH-STEP CONTACTS; AND DEAD INDEX CONTACT MEAND INCLUDED IN SAID SEARCH-STEP CONTACTS FOR AUTOMATICALLY STOPPONG AND STEPPING ACTION WHEN ALL SENSING RELAYS ARE IN THE SECOND-NAMED OPERATIVE CONDITION.