Automatic electronic communication switching exchange

Claim 1

AN ELECTRONIC SWITCHING OFFICE FOR A TWO-WAY COMMUNICATION SYSTEM INCLUDING A SWITCHING MATRIX COMPRISING THE TERMINATING PORTIONS OF A PLURALITY OF SUBSCRIBER LINES, A PLURALITY OF TRANSMISSION LINKS CROSSING SAID TERMINATING LINE PORTIONS AT DIFFERENT POINTS; A FIRST PLURALITY OF PULSE GENERATING MEANS, RESPONSIVE TO SIGNALS INITIATED BY A SUBSCRIBER ASSOCIATED WITH ONE OF THE SUBSCRIBER LINES DESIRING TO COMMUNICATE WITH ANOTHER SUBSCRIBER ASSOCIATED WITH ANOTHER SUBSTRICKER LINE, TO GENERATE A PULSE OF ONE POLARITY AND A GIVEN AMPLITUDE; A SECOND PLURALITY OF PULSE GENERATING MEANS FOR GENERATING A PULSE OF THE SAME POLARITY AND OF AN AMPLITUDE LESS THAN THAT OF THE PULSES OF SAID FIRST GENERATING MEANS; ONE OF SAID FIRST AND SECOND PLURALITY OF PULSE GENERATING MEANS BEING CONNECTED TO EACH OF SAID SUBSCRIBER LINES; A THIRD PLURALITY OF PULSE GENERATING MEANS EACH FOR GENERATING A PULSE OF REVERSE POLARITY AND AN AMPLITUDE LESS THAN THAT OF THE PULSES OF SAID FIRST GENERATING MEANS; ONE OF SAID THIRD PULSE GENERATING MEANS BEING CONNECTED TO EACH OF SAID TRANSMISSION LINKS; AND BISTABLE CROSSPOINT SWITCHING MEANS INCLUDING A SINGLE SWITCHING ELEMENT AT THE INTERSECTION OF THE LINES AND LINKS FOR CONNECTING ONE OF SAID LINES TO THE ADJACENT LINK UPON APPLICATION OF ONE OF SAID FIRST PULSES TO ONE OF SAID LINES OR UPON THE SIMULTANEOUS APPLICATION OF ONE OF SAID SECOND PULSES TO ONE OF SAID LINES AND ONE OF SAID THIRD PULSES TO ONE OF SAID LINKS, WHEREBY THE CROSSPOINT SWITCH AT THE INTERSECTION OF A CALLING LINE AND AN IDLE LINK IS SWITCHED ON IN RESPONSE TO ONE OF SAID FIRST PULSES, THEREBY SEIZING THE LINK TO WHICH THAT SWITCH IS CONNECTED, THE SEIZURE OF THE LINK CAUSING ONE OF THE THIRD PULSES TO BE TRANSMITTED OVER THE SEIZE LINK, AND SIMULTANEOUSLY ONE OF THE SECOND PULSES TO BE TRANSMITTED OVER THE CALLED LINE ONLY IF THE CALLED LINE IS NOT BUSY, THE COMBINED EFFECT OF THE SECOND AND THIRD PULSES BEING SUFFICIENT TO CAUSE OPERATION OF THE SWITCH AT THE INTERSECTION OF THE CALLED LINE AND THE SEIZED LINK.