Direct station selection circuit

Claim 2

A direct station selection apparatus adapted for use in a key telephone system in which at least one station of the system is equipped with an audio receiver in addition to the speaker of the station telephone instrument, comprising a second station having means associated with said second station for directly connecting the second station to the audio receiver at the one station regardless of the condition of the one station as busy or idle, means responsive to the direct connection for initiating an audio signal for transmission to the additional audio receiver and to the station instrument of said one station, and means responsive to said connection for automatically placing on hold any telephone line in communication with said second station.

Claim 3

A direct station selection apparatus as claimed in claim 1, wherein said direct connecting means comprises manually operable switch means at said second station.

Claim 4

A direct station selection apparatus as claimed in claim 2 wherein there are a plurality of stations on said key system each equipped with an additional receiver, and a plurality of manually operable switch means at said second station, each said switch means being directly connected to an individual receiver at another said plurality of stations.

Claim 5

A direct station selection apparatus in a key telephone system to provide a direct connection between a predetermined calling station and any one of a plurality of stations, said apparatus comprising a key console at said calling station with a separate key at said console for each of said plurality of stations, an A lead path from said calling station to a further station in communication with said calling station, a control circuit associated with said console and having connection in multiple to the keys thereat, said control circuit including: means for maintaining said A lead path for the flow of current therethrough, a relay responsive to operation of a selected one of said keys for completing a battery feed path between the calling station and the one station of the operated key and for completing a talking path from the calling station to the one station, further means responsive to operation of said key for blocking the flow of current through said A lead path to thereby place a hold condition on said further station, reset means for sensing a restoration of current in the battery feed path for removing the blockage of said A lead path for current flow.

Claim 6

A direct station selection apparatus in a key telephone system to provide a direct connection between a predetermined calling station and any one of a plurality of stations, said apparatus comprising a key console at said calling station with a separate key at said console for each of said plurality of stations, an A lead path from said calling station to a further station in communication with said calling station, a control circuit associated with said console and having connection in multiple to the keys thereat, said control circuit including: means for maintaining said A lead path for the flow of current therethrough, a relay responsive to operation of a selected one of said keys for completing a battery feed path between the calling station and the one station of the operated key and for completing a talking path from the calling station to the one station, further means responsive to operation of said key for blocking the flow of current through said A lead path to thereby place a hold condition on said further station, reset means for sensing a restoration of current in the battery feed path for removing the blockage of said A lead path for current flow.

Claim 7

A direct station selection circuit as claimed in claim 4, wherein said reset means includes a bistable latch settable into a first condition on operation of said key and settable into a second condition responsive to restoration of said relay and the sequential release and restoration of said current sensing means.