Signaling system employing a remotely controlled switch

Claim 1

IN A COMMUNICATION SYSTEM INCLUDING A CENTRAL STATION AND AT LEAST ONE REMOTE STATION, A SIGNALLING SYSTEM FOR PRODUCING A SIGNAL AT THE CENTRAL STATION FROM THE REMOTE STATION AND FOR CANCELLING THE SIGNAL FROM THE CENTRAL STATION, SAID SIGNALLING SYSTEM COMPRISING A SIGNALLING SWITCH AT THE REMOTE STATION, MANUAL MEANS FOR CLOSING SAID SWITCH, LATCH MEANS FOR HOLDING SAID SWITCH IN THE CLOSED POSITION, MEANS FOR RELEASING AND OPENING SAID SWITCH WHEN A RELATIVE HEAVY CURRENT IS SUPPLIED THERETO, SAID RELEASING AND OPENING MEANS BEING EFFECTIVE TO RELEASE AND OPEN SAID SWITCH REGARDLESS OF THE POSITION OF SAID MANUAL MEANS, A SOURCE OF POWER, SIGNAL APPARATUS AT THE CENTRAL STATION, MEANS FOR CONNECTING ELECTRICALLY SAID SOURCE OF POWER, SAID SIGNAL APPARATUS, AND SAID SIGNALLING SWITCH WHEREBY SAID SIGNAL APPARATUS WILL OPERATE WHEN SAID SWITCH IS CLOSED AND SAID SIGNAL APPARATUS WILL BE INOPERATIVE WHEN SAID SWITCH IS OPEN, AND SWITCH MEANS CONNECTED ELECTRICALLY IN PARALLEL WITH SAID SIGNAL APPARATUS FOR SUPPLYING THE RELATIVELY HEAVY CURRENT TO SAID RELEASING AND OPENING MEANS AT A PREDETERMINED TIME TO OPEN SAID SIGNALLING SWITCH AND TO RENDER SAID SIGNAL INOPERATIVE.