Inter-communication systems

Claim 1

FOR AN INTERCOMMUNICATION SYSTEM PERMITTING ANY ONE OF A NUMBER OF EXTENSIONS AT ONE END OF A COMMUNICATION PATH TO OBTAIN ACCESS OVER SAID PATH TO ANY ONE OF A NUMBER OF EXTENSIONS AT THE OTHER END, APPARATUS FOR ONE END OF SAID PATH COMPRISING IN COMBINATION: A PLURALITY OF FIRST SWITCHING MEANS PERTAINING TO EACH OF THE EXTENSIONS AT SAID END AND EACH OPERABLE FOR AFFORDING ACCESS OF ITS EXTENSION TO THE COMMUNICATION PATH TO THE EXCLUSION OF ALL OTHER EXTENSIONS AT THE SAME END; PULSE GENERATING MEANS OPERABLE TO APPLY A PULSE TRAIN TO THE COMMUNICATION PATH CONSEQUENT UPON OPERATION OF A FIRST SWITCHING MEANS PERTAINING TO A CALLING EXTENSION AT THIS END; A PLURALITY OF SECOND SWITCHING MEANS PERTAINING ONE TO EACH EXTENSION AT THE OTHER END OF THE PATH; CALLING MEANS AT EACH EXTENSION FOR CONTEMPORANEOUSLY OPERATING THE FIRST SWITCHING MEANS PERTAINING TO THAT EXTENSION WHEN CALLING AND THE PARTICULAR SECOND SWITCHING MEANS WHICH PERTAINS TO THE EXTENSION AT THE OTHER END WHICH IS BEING CALLED; PULSE DETERMINING MEANS CONTROLLED BY AN OPERATED SECOND SWITCHING MEANS FOR DETERMINING, ACCORDING TO THE PARTICULAR CALLED EXTENSION TO WHICH IT RELATES, THE NUMBER OF PULSES IN A PULSE TRAIN APPLIED TO THE COMMUNICATION PATH BY THE PULSE GENERATING MEANS; AND SELECTING MEANS FOR CAUSING SELECTIVE OPERATION OF A PARTICULAR FIRST SWITCHING MEANS INDEPENDENTLY OF SAID CALLING MEANS IN RESPONSE TO A PULSE TRAIN RECEIVED OVER THE COMMUNICATION PATH FROM THE OTHER END, THE NUMBER OF PULSES IN SUCH RECEIVED PULSE TRAIN IDENTIFYING A PARTICULAR EXTENSION THAT IS BEING CALLED BY A CALLING EXTENSION AT THE OTHER END, AND THE PARTICULAR FIRST SWITCHING MEANS WHICH IS CAUSED TO BE OPERATED BY THE SELECTING MEANS BEING THAT WHICH PERTAINS TO THE EXTENSION THUS IDENTIFIED.