Automatic train operation systems

Claim 1

AN AUTOMATIC TRAIN OPERATION SYSTEM FOR A TRAIN TRAVELING THROUGH RAILWAY TERRITORY PROVIDED WITH A PLURALITY OF STATIONS AT PRESELECTED LOCATIONS WITHIN THE TERRITORY AND EACH INCLUDING A STATION PLATFORM AREA, SAID SYSTEM COMPRISING, IN COMBINATION, MEANS FOR TRANSMITTING TO THE TRAIN A FIRST DISTINCT SIGNAL WHEN THE TRAIN IS WITHIN ANY ONE OF FIRST PRESCRIBED TRACK STRETCHES BETWEEN SAID STATIONS, MEANS FOR TRANSMITTING TO THE TRAIN A SECOND DISTINCT SIGNAL WHEN THE TRAIN IS WITHIN ANY ONE OF SECOND PRESCRIBED TRACK STRETCHES EACH IN APPROACH TO A STATION PLATFORM AREA, MEANS FOR TRANSMITTING TO THE TRAIN A THIRD DISTINCT SIGNAL WHEN THE TRAIN IS WITHIN ANY ONE OF THIRD PRESCRIBED TRACK STRETCHES EACH WITHIN A STATION PLATFORM AREA, A TIMING DEVICE FOR EACH SAID THIRD TRACK STRETCH, MEANS CONTROLLED BY THE ENTRANCE OF THE TRAIN INTO EACH SAID THIRD TRACK STRETCH FOR INITIATING THE TIMING CYCLE OF THE TIMING DEVICE FOR THAT TRACK STRETCH, MEANS CONTROLLED BY EACH SAID TIMING DEVICE AT THE END OF ITS TIMING CYCLE FOR INTERRUPTING THE TRANSMISSION TO SAID TRAIN OF SAID THIRD SIGNAL AND TRANSMITING TO THE TRAIN SAID FIRST SIGNAL; SIGNAL RECEIVING APPARATUS ON SAID TRAIN SELECTIVELY RESPONSIVE TO THE RECEIPT OF SAID FIRST, SECOND, AND THIRD DISTINCT SIGNALS; A SPEED RESPONSIVE GOVERNOR ON SAID TRAIN, MEANS CONTROLLED BY SAID SIGNAL RECEIVING APPARATUS AND SAID GOVERNOR FOR CONTROLLING THE SPEED OF SAID TRAIN TO AND MAINTAINING IT WITHIN A FIRST DISTINCT SPEED RANGE WHEN SAID FIRST SIGNAL IS RECEIVED, MEANS CONTROLLED BY SAID SIGNAL RECEIVING APPARATUS AND SAID GOVERNOR FOR CONTROLLING THE SPEED OF SAID TRAIN TO AND MAINTAINING IT WITHIN A SECOND DISTINCT SPEED RANGE WHEN SAID SECOND SIGNAL IS RECEIVED, AND MEANS CONTROLLED BY SAID SIGNAL RECEIVING APPARATUS FOR CONTROLLING THE OPENING OF THE DOORS OF SAID TRAIN WHEN SAID THIRD SIGNAL IS RECEIVED AND THE CLOSING OF THE DOORS OF THE TRAIN WHEN THE RECEIPT OF THE THIRD SIGNAL IS THEREAFTER INTERRUPTED.