Electric temperature control and fire alarm system

Claim 1

AN ELECTRIC TEMPERATURE CONTROL AND FIRE ALARM SYSTEM, COMPRISING AN ELECTRIC D.C. SOURCE ARRANGED AT A CENTRAL STATION, FIRST AND SECOND WATCHING CONDUITS FORMING CLOSED CIRCUITS IN PARALLEL FROM ONE POLE OF SAID ELECTRIC SOURCE VIA A LOCAL WATCHING STATION AND BACK TO THE OTHER POLE OF SAID SOURCE, A THERMOSENSITIVE MEANS HAVING FIRST, SECOND AND THIRD CONTACT WIRES, A RESISTOR, SAID FIRST CONTACT WIRE BEING DIRECTLY CONNECTED TO SAID FIRST WATCHING CONDUIT, SAID SECOND CONTACT WIRE BEING CONNECTED TO SAID SECOND WATCHING CONDUIT THROUGH SAID RESISTOR, AND SAID THIRD CONTACT WIRE BEING DIRECTLY CONNECTED TO SAID SECOND WATCHING CONDUIT, SAID THERMOSENSITIVE MEANS BEING ADAPTED TO INSULATE SAID FIRST CONTACT WIRE FROM SAID SECOND AND THIRD CONTACT WIRES AT NORMAL AMBIENT TEMPERATURE AND TO PROVIDE A CONNECTION BETWEEN SAID FIRST AND SAID SECOND CONTACT WIRES UPON A TEMPERATURE INCREASE TO A FIRST PRE-SELECTED LEVEL IN SAID THERMOSENSITIVE MEANS AND FURTHER TO PROVIDE A CONNECTION BETWEEN SAID FIRST AND SAID THIRD CONTACT WIRES UPON A TEMPERATURE INCREASE TO A SECOND HIGHER PRE-SELECTED LEVEL IN SAID THERMOSENSITIVE MEANS, A HIGH RESISTANCE RELAY, AND A LOW RESISTANCE RELAY, SAID RELAYS BEING CONNECTED IN SERIES WITH SAID FIRST WATCHING CIRCUIT TO PROVIDE THAT THE FIRST-MENTIONED RELAY CLOSES AND THE SECOND-MENTIONED RELAY OPENS WHEN THE TEMPERATURE IN THE LOCAL WATCHING STATION IS AT A NORMAL AMBIENT LEVEL, AND TO PROVIDE THAT THE SECOND-MENTIONED RELAY CLOSED IF THE TEMPERATURE IN SAID STATION INCREASES TO THE FIRST-MENTIONED PRE-SELECTED LEVE, AND TO PROVIDE THAT THE FIRST-MENTIONED RELAY OPENS IF THE TEMPERATURE IN SAID STATION INCREASES TO THE SECONDMENTIONED PRE-SELECTED LEVEL, SAID SYSTEM FURTHER COMPRISING A THIRD RELAY CONNECTED IN SERIES WITH SAID SECOND WATCHING CONDUIT, SAID THIRD RELAY BEING CHARGED WITH CURRENT THROUGH A BACK CONTACT OF SAID FIRST RELAY AND COMPRISING BACK CONTACTS FOR CLOSING SAID FIRST RELAY AT AN INTERRUPTION OF SAID FIRST WATCHING CONDUIT AND TO EFFECT AN INTERCONNECTION OF SAID WATCHING CONDUITS AT AN INTERRUPTION IN EACH OF SAID WATCHING CONDUITS WHEREBY A SINGLE WATCHING CIRCUIT IS SET UP WHICH IS INTERRUPTED AT THE THERMOSENSITIVE MEANS AT NORMAL AMBIENT TEMPERATURE AND IS CLOSED THEREBY AT A TEMPERATURE INCREASE TO SAID FIRST AND SECOND ORDER PRESELECTED LEVELS.