Conference call circuit

Claim 2

In a telephone switching system, the combination comprising conference call circuit means having a plurality of access port circuits, means comprising at least one voice path associated with each of said port circuits for selectively controlling a private conversation path and a common conversation path, means for initially interconnecting a convening party and each participant party in a sequence via said private conversation path, means for thereafter transferring said participant party to said common conference path, wherein said controlling means comprises a pair of mixing busses and voice gates means for selectively connecting each of said port circuits to either of said mixing busses, and wherein each of said voice gate means comprises a diode having biasing means connected thereto on either side thereof and means selectively back biasing one of said diodes while forward biasing the other of said diodes.

Claim 3

The switching system of claim 1 and means wherein said transferring means is controlled by a hook-switch flash.

Claim 4

A conference call circuit having means for sequentially introducing a plurality of subscriber lines into a common speech channel, means for initially interconnecting at least two of said subscriber lines in a private speech channel before said introduction into said common speech channel, means for thereafter transferring said two subscribers from said private speech channel to said common speech channel and means for operating said conference call circuit to set up a ''''meet-me'''' conference call.

Claim 5

A conference call circuit having means for sequentially introducing a plurality of subscriber lines into a common speech channel, means for initially interconnecting at least two of said subscriber lines in a private speech channel before said introduction into said common speech channel, means for thereafter transferring said two subscribers from said private speech channel to said common speech channel and means for operating said conference call circuit to set up a ''''meet-me'''' conference call.

Claim 6

The conference call circuit of claim 3 and attendant control means, and means for setting up a conference call from said attendant control means.

Claim 7

The conference call circuit of claim 4 and means for connecting a trunk circuit to said conference call circuit, and means for thereafter selectively releasing said trunk circuit without releasing either said conference call circuit or other subscriber lines interconnected in said conference call.

Claim 8

A telephone switching system comprising a plurality of conference control circuits, each such circuit individually associatable with a party participating in a conference to provide supervisory signals to the party so associated, one of said circuits responsive to a party convening a conference for controlling the completing of the connection to a called party over a private conversation path to said called party, means in the associated control circuits for transferring said convening and called party to a common conference path simultaneously, means in the circuit associated with said called party for holding said conference path following release therefrom of said convening party to allow said convening party to add other parties to said conference, each successive other party being connected individually to said convening party over said private conversation path for subsequent transfer to said common conference path.

Claim 9

A telephone switching system comprising a plurality of conference control circuits, each such circuit individually associatable with a party participating in a conference to provide supervisory signals to the party so associated, one of said circuits responsive to a party convening a conference for controlling the completing of the connection to a called party over a private conversation path to said called party, means in the associated control circuits for transferring said convening and called party to a common conference path simultaneously, means in the circuit associated with said called party for holding said conference path following release therefrom of said convening party to allow said convening party to add other parties to said conference, each successive other party being connected individually to said convening party over said private conversation path for subsequent transfer to said common conference path.

Claim 10

A system as claimed in claim 6, wherein said transferring means is controlled by a flashing of the hook switch by the convening party.