Track fullness system

Claim 1

IN A RAILWAY CAR STORAGE YARD INCLUDING A SINGLE TRACK CONNECTING INTO A PLURALITY OF STORAGE TRACKS, A SYSTEM FOR INDICATING THE EMPTY CAR SPACE BETWEEN THE ENTRANCE END OF EACH STORAGE TRACK AND THE NEAREST CAR STANDING IN SUCH TRACK, SAID SYSTEM COMPRISING, MEANS CONTROLLED BY EACH CUT OF CARS TRAVERSING SAID SINGLE TRACK FOR ADJUSTING A FIST SIGNAL FOR THE STORAGE TRACK TO WHICH THE RESPECTIVE CUT IS DESTINED IN ACCORDANCE WITH THE NUMBER OF CARS IN THAT CUT, SAID SIGNAL BEING ADJUSTED PROPORTIONATELY TO THE TOTAL NUMBER OF CARS ROUTED TO THAT STORAGE TRACK; MEANS FOR PERIODICALLY SELECTING EACH STORAGE TRACK AND ADJUSTING A SECOND SIGNAL FOR THE TRACK PROPORTIONATELY TO THE EMPTY CAR SPACE BETWEEN THE ENTRANCE END OF SUCH TRACK AND THE NEAREST CAR STANDING IN THE TRACK, MEANS FOR COMPARING SAID FIRST AND SECOND SIGNALS FOR THE SELECTED STORAGE TRACK AND DERIVING A THIRD SIGNAL FOR THAT TRACK REPRESENTATIVE OF THE DIFFERENCE IN VALUE AND POLARITY BETWEEN THE TWO COMPARED SIGNALS, MOTION DETECTOR MEANS RESPONSIVE TO THE DETECTION OF A MOVING CAR IN THE SELECTED STORAGE TRACK FOR INTERRUPTING THE COMPARISON OF THE FIRST AND SECOND SIGNALS FOR THAT SELECTED STORAGE TRACK, AND MEANS CONTROLLED BY EACH DERIVED THIRD SIGNAL IN ACCORDANCE WITH ITS VALUE AND POLARITY FOR READJUSTING THE FIRST SIGNAL ADJUSTING MEANS FOR THE CORRESPONDING TRACK TO INCREASE OR DECREASE SAID FIRST SIGNALS TO BRING SUCH FIRST SIGNAL SUBSTANTIALLY INTO AGREEMENT WITH THE SECOND SIGNAL FOR THAT TRACK.