Crosspoint switching array having marker pulse measuring means

Claim 1

IN A COMMUNICATION SWITCHING SYSTEM, A FIRST SET OF TERMINALS, A SECOND SET OF TERMINALS, A PLURALITY OF SWITCHING STAGES ARRANGED IN TANDEM FOR SELECTIVELY ELECTRICALLY CONNECTING TERMINALS OF THE FIRST SET WITH TERMINALS OF THE SECOND SET, EACH OF SAID STAGES COMPRISING A PLURALITY OF RELAYS ARRANGED IN COORDINATE ARRAYS, A UNIDIRECTIONAL DEVICE INDIVIDUAL TO EACH OF SAID RELAYS AND CONNECTED IN SERIES WITH THE WINDING THEREOF, AT THE COORDINATE POINTS OF EACH OF SAID ARRAYS, LINKS INTERCONNECTING ADJACENT STAGES; MEANS TO APPLY A FIRST MARKING POTENTIAL TO A SELECTED TERMINAL OF THE FIRST SET, SCANNING MEANS INCLUDING DETECTING DEVICES COUPLED TO THE TERMINALS OF THE SECOND SET TO SCAN SAID SECOND SET TO DETECT SAID FIRST MARKING POTENTIAL AND STOP THE SCANNING MEANS AT THE CORRESPONDING TERMINAL OF THE SECOND SET; TIMING MEANS CONNECTED TO THE SCANNING MEANS TO START RESPONSIVE TO SAID DETECTION OF THE FIRST MARKING POTENTIAL TO MEASURE A PREDETERMINED TIME INTERVAL, COUNTING MEANS IN SAID TIMING MEANS, SAID COUNTING MEANS REMAINING STOPPED DURING THIS INTERVAL ONLY SO LONG AS SAID MARKING POTENTIAL CONTINUES TO BE DETECTED AND BEING STARTED UPON THE ABSENCE OF THE MARKING POTENTIAL TO CONTINUE THE SCAN OF OTHER DETECTING DEVICES FOR THE MARKING POTENTIAL; AND MEANS RESPONSIVE TO THE CONTINUATION OF THE MARKING POTENTIAL FOR THE DURATION OF SAID INTERVAL AT ONE COUNTING POSITION TO CAUSE THE TIMING ARRANGEMENT TO GENERATE A SIGNAL WHICH LOCKS THE COUNTING MEANS IN ITS POSITION AND ALSO CAUSES A SECOND MARKING POTENTIAL TO BE APPLIED TO THE SELECTED TERMINAL OF THE SECOND SET CORRESPONDING TO THE COUNTING MEANS POSITION TO PRODUCE A POTENTIAL DIFFERENCE BETWEEN THE FIRST AND SECOND MARKING POTENTIALS THROUGH THE SWITCHING STAGES IN THE FORWARD DIRECTION OF SAID UNIDIRECTIONAL DEVICES BETWEEN THE TWO SELECTED TERMINALS THROUGH A SERIES PATH INCLUDING THE WINDING OF ONE COORDINATE POINT RELAY OF EACH OF SAID STAGES, WHICH CAUSES SAID RELAYS IN THE PATH BETWEEN THE TWO SELECTED TERMINALS TO OPERATE AND THEREBY ESTABLISH A COMMUNICATION PATH; WHEREBY NOISE PULSES HAVING A DURATION LESS THAN SAID GIVEN INTERVAL INDUCED IN THE OPERATE PATH OF THE SWITCHING STAGES ARE NOT EFFECTIVE TO CAUSE THE SCANNING MEANS TO SELECT AND ESTABLISH A CONNECTION.