Selectably controllable announcement system

Claim 2

In a telephone switching system having a plurality of central office switching centers in which connections are established between a calling subscriber at a calling switching center and a called subscriber at a called switching center in response to directory number representative signals transmitted over a trunk circuit between the calling and called switching centers, the combination comprising a plurality of terminating circuits at a called one of said switching centers, each terminating circuit assigned a unique code, a register at said called one of said switching centers, means for establishing a first connection from a calling one of said switching centers over a first one of said trunk circuits to said register, means in said connected register for receiving directory number representative signals over said connected first trunk from said calling switching center and for translating said received signals into one of said codes representative of a called one of said terminating circuits, means controlled by said connected register for establishing a second connection between said first trunk associated with said calling switching center and said terminating circuit associated with said translated code, and means controlled by said second connection establishing means and responsive to said establishment of said second connection for releasing said first connection between said first trunk and said connected register and for transferring control of said second connection establishing means from said connected register to said connected first trunk circuit.

Claim 3

The invention set forth in claim 1 wherein said second connection establishing means includes a matrix network for connecting any of said trunks to any of said terminating circuits, and a matrix control circuit responsive to said register translation means for controlling connections through said matrix network.

Claim 4

The invention set forth in claim 1 wherein said control transfer means includes a signal path from said second connection establishing means via said first connection and through said connected register to said first trunk circuit.

Claim 5

The invention set forth in claim 1 wherein each said terminating circuit is operable to provide a unique message, means responsive to the establishment of said second connection to a called one of said terminating circuits for transmitting a call charging signal to said calling switching center, and means concurrently operative with the transmitting of said charging signal for enabling the transmission of said called terminating circuit message over said first trunk circuit to said calling switching center.

Claim 6

The invention set forth in claim 4 wherein said second connection is established to a special terminating circuit when said translated code corresponds to an unassigned terminating circuit.

Claim 7

The invention set forth in claim 5 further comprising means responsive to the establishment of said second connection to said special terminating circuit for inhibiting said transmission of said call charging signal while still enabling the transmission of said message associated with said special terminating circuit over said first trunk circuit to said calling switching center.

Claim 8

In a unidirectional central office switching center in which only incoming connections from distant central office switching centers may be established, the combination comprising a plurality of trunk circuits interconnecting said unidirectional central office with said distant central offices; a plurality of registers; a plurality of terminating stations; a first switching stage operable for establishing connections from calling ones of said central offices via activated ones of said trunk circuits to any of said registers; a second switching stage operable for establishing direct connections from activated ones of said trunk circuits to any of said terminating stations; control means in said first switching stage for determining the idle and priority status of any of said registers and for enabling a connection through said first switching stage from an activated one of said trunk circuits to the highest priority idle register; means in said first switching stage control means responsive to the establishment of said connection for transferring control of said connection exclusively to said connected register; said connected register comprising means concurrently operable with the enabling of said transfer means for enabling the transmission of called station designations from said connected calling switching office over said activated trunk circuit, means for receiving said designations, means for translating a received designation into a code representative of a called terminating station, and means controlled by said translating means for seizing said second switching stage; control means in said second switching stage responsive to a seizure from said connected register for preparing a calling connection through said second switching stage to said called terminating station corresponding to said translated code, and means including said activated trunk circuit for completing said calling connection through said second switching stage from said called terminating station to said activated trunk circuit.

Claim 9

In a unidirectional central office switching center in which only incoming connections from distant central office switching centers may be established, the combination comprising a plurality of trunk circuits interconnecting said unidirectional central office with said distant central offices; a plurality of registers; a plurality of terminating stations; a first switching stage operable for establishing connections from calling ones of said central offices via activated ones of said trunk circuits to any of said registers; a second switching stage operable for establishing direct connections from activated ones of said trunk circuits to any of said terminating stations; control means in said first switching stage for determining the idle and priority status of any of said registers and for enabling a connection through said first switching stage from an activated one of said trunk circuits to the highest priority idle register; means in said first switching stage control means responsive to the establishment of said connection for transferring control of said connection exclusively to said connected register; said connected register comprising means concurrently operable with the enabling of said transfer means for enabling the transmission of called station designations from said connected calling switching office over said activated trunk circuit, means for receiving said designations, means for translating a received designation into a code representative of a called terminating station, and means controlled by said translating means for seizing said second switching stage; control means in said second switching stage responsive to a seizure from said connected register for preparing a calling connection through said second switching stage to said called terminating station corresponding to said translated code, and means including said activated trunk circuit for completing said calling connection through said second switching stage from said called terminating station to said activated trunk circuit.

Claim 10

The invention set forth in claim 7 further comprising means in said second switching stage control means responsive to said establishment of said calling connection for transferring control of said calling connection exclusively to said activated incoming trunk, and means operable in response to the enabling of said transfer control means for releasing said connection thRough said first switching stage so as to disassociate said connected register from said calling connection.

Claim 11

The invention set forth in claim 7 wherein said calling connection preparation means includes means for applying a signal through said connected register and over said first stage connection to said activated incoming trunk, and means for returning a signal from said activated incoming trunk over said first stage connection and through said translating means of said connected register to said second switching stage control means.

Claim 12

The invention set forth in claim 9 wherein said second switching stage connection completing means further includes means for applying signals from said activated trunk circuit directly to said second switching stage control means.

Claim 13

The invention set forth in claim 10 wherein said second switching stage comprises a crossbar switch having select magnets controlling horizontal multiples each associated with individual ones of said terminating stations and hold magnets controlling vertical multiples each associated with individual ones of said incoming trunk circuits, and wherein said transfer control means includes a direct connection between said incoming trunk circuit and an isolated crossbar switch contact on the vertical multiple controlled by said hold magnet associated with said incoming trunk circuit.

Claim 14

A central office telephone switching system comprising a plurality of trunks, a plurality of registers, a plurality of terminal circuits each identified by a unique code, a register link responsive to the activation of one of said trunks for establishing a first connection from said activated trunk to an idle one of said registers and for transferring to said connected register certain trunk identification information, means in said connected register responsive to signals transmitted over said connected trunk for translating said signals into codes representative of a called terminal circuit, a terminal circuit link controlled directly by said connected register and responsive jointly to trunk identification information from said connected register and to a translated code from said connected register for preparing a second connection from said activated trunk to said called terminal circuit, means for transmitting a signal over said first connection from said terminal circuit link to said activated trunk to mark a position in said terminal circuit link associated with said activated trunk and means responsive to said marking signal for establishing an exclusive connection between said activated trunk and said called terminal circuit.

Claim 15

A central office telephone switching system comprising a plurality of trunks, a plurality of registers, a plurality of terminal circuits each identified by a unique code, a register link responsive to the activation of one of said trunks for establishing a first connection from said activated trunk to an idle one of said registers and for transferring to said connected register certain trunk identification information, means in said connected register responsive to signals transmitted over said connected trunk for translating said signals into codes representative of a called terminal circuit, a terminal circuit link controlled directly by said connected register and responsive jointly to trunk identification information from said connected register and to a translated code from said connected register for preparing a second connection from said activated trunk to said called terminal circuit, means for transmitting a signal over said first connection from said terminal circuit link to said activated trunk to mark a position in said terminal circuit link associated with said activated trunk and means responsive to said marking signal for establishing an exclusive connection between said activated trunk and said called terminal circuit.

Claim 16

The invention set forth in claim 12 wherein said last-mentioned means includes means in said activated trunk for detecting said last established connection and for releasing said first connection from said activated trunk to said connected register.

Claim 17

The invention set forth in claim 12 wherein said register translation means is further arranged for translating signals representative of nonassigned terminal circuits into predesignated codes representative of special terminal circuits.

Claim 18

The invention set forth in claim 14 further comprising means for returning a start signal over said activated trunk for a fixed interval prior to enabling transmission over said activated trunk from said connected terminal circuit associated with said translated code.

Claim 19

The invention set forth in claim 15 further comprising means concurrently responsive to the end of said start signal interval and to connection to a terminal circuit identified by an assigned code for returning call charging signals over said activated trunk and for enabling transmission from said activated trunk to said connected terminal circuit.

Claim 20

The invention set forth in claim 16 further comprising means concurrently responsive to the end of said start signal interval and to connection to a terminal circuit identified by a predesignated code for inhibitiNg said transmission of said call charging signals while still enabling from said connected terminal circuit to said activated trunk.

Claim 21

The invention set forth in claim 16 wherein said terminal circuits are each arranged with a repetitive announcement machine, said transmission enabling means includes means for ensuring that at least one full announcement cycle is returned over the activated trunk, and means for preventing more than two announcement cycles from being returned over said activated trunk.

Claim 22

In a central office switching system in which connections are completed to called stations in accordance with unique directory numbers transmitted from other central offices over interoffice trunks, the combination comprising a first register link having vertical and horizontal multiples wherein individual interoffice trunks in a first group of said interoffice trunks are each associated with one of said vertical multiples, a second register link having vertical and horizontal multiples wherein individual interoffice trunks in a second group of said interoffice trunks are each associated with one of said vertical multiples, a plurality of incoming registers each associated with one of said horizontal multiples in each of said first and second register links, connection control means responsive to a calling one of said interoffice trunks for establishing a connection from said calling interoffice trunk through said register link associated with said calling interoffice trunk to an idle first one of said registers, means in a said connected first incoming register for receiving signals representative of a called directory number over said connected calling interoffice trunk and for translating received ones of said signals into a control signal representative of a called one of said stations, a first announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said first group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in a first group of said stations are each associated with one of said horizontal multiples, a second announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said first group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in a second group of said stations are each associated with one of said horizontal multiples, a third announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said second group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in said first group of said stations are each associated with one of said horizontal multiples, a fourth announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said second group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in said second group of said stations are each associated with one of said horizontal multiples, means controlled by said connected incoming register translation means for enabling the announcement link corresponding jointly to the group with which said called station is associated and the group with which said connected calling incoming trunk is associated, and means controlled jointly by said enabled one of said announcement links and by said register translation means for establishing a connection from said calling incoming trunk to said called station through said enabled link.

Claim 23

In a central office switching system in which connections are completed to called stations in accordance with unique directory numbers transmitted from other central offices over interoffice trunks, the combination comprising a first register link having vertical and horizontal multiples wherein individual interoffice trunks in a first group of said interoffice trunks are each associated with one of said vertical multiples, a second register link having vertical and horizontal multiples wherein individual interoffice trunks in a second group of said interoffice trunks are each associated with one of said vertical multiples, a plurality of incoming registers each associated with one of said horizontal multiples in each of said first and second register links, connection control means responsive to a calling one of said interoffice trunks for establishing a connection from said calling interoffice trunk through said register link associated with said calling interoffice trunk to an idle first one of said registers, means in a said connected first incoming register for receiving signals representative of a called directory number over said connected calling interoffice trunk and for translating received ones of said signals into a control signal representative of a called one of said stations, a first announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said first group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in a first group of said stations are each associated with one of said horizontal multiples, a second announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said first group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in a second group of said stations are each associated with one of said horizontal multiples, a third announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said second group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in said first group of said stations are each associated with one of said horizontal multiples, a fourth announcement link having vertical and horizontal multiples wherein individual interoffice trunks in said second group of said interoffice trunks are each associated with one of said vertical multiples and wherein individual ones of said stations in said second group of said stations are each associated with one of said horizontal multiples, means controlled by said connected incoming register translation means for enabling the announcement link corresponding jointly to the group with which said called station is associated and the group with which said connected calling incoming trunk is associated, and means controlled jointly by said enabled one of said announcement links and by said register translation means for establishing a connection from said calling incoming trunk to said called station through said enabled link.

Claim 24

The invention set forth in claim 19 wherein said last-mentioned means includes a signal path from said calling incoming trunk through said connected incoming register for communicating said called station information and a signal path direct from said calling inteRoffice trunk for communicating said trunk identification.

Claim 25

The invention set forth in claim 20 further comprising means operative in response to the establishment of said connection through said announcement link for releasing said connection between said calling interoffice trunk and said connected incoming register so that said register is available to handle other terminating connections.

Claim 26

The invention set forth in claim 21 wherein said connection control means is arranged to allow only one calling connection to be established in any one incoming register link at a time while allowing simultaneous calling connections to be established in different incoming register links, and means interposed between said incoming registers and said announcement links for insuring that connections through said announcement links are enabled by only one register at a time.

Claim 27

The invention set forth in claim 22 wherein each said called station includes an announcement machine for returning a message over a connected incoming trunk, and means controlled by said incoming register translation means for translating signals corresponding to unassigned codes into a code corresponding to a predetermined one of said announcement machines so that a predetermined message will be returned over a connected incoming trunk when a directory number is received which is not translatable into a working code.

Claim 28

An announcement switching center for providing selected announcements to trunks interconnecting the announcement switching center with a plurality of other switching centers comprising a plurality of registers for receiving control signals from said trunks, a register link for connecting said registers to said trunks over a first connection from said trunks, a plurality of announcement circuits, an announcement link, and means controlled by said announcement link and responsive to control information in one of said registers from one of said trunks for transmitting a signal from said announcement link through a first established connection from said one register to said one trunk and back to said announcement link for establishing a second connection from said one trunk to a selected announcement circuit.

Claim 29

An announcement switching center for providing selected announcements to trunks interconnecting the announcement switching center with a plurality of other switching centers comprising a plurality of registers for receiving control signals from said trunks, a register link for connecting said registers to said trunks over a first connection from said trunks, a plurality of announcement circuits, an announcement link, and means controlled by said announcement link and responsive to control information in one of said registers from one of said trunks for transmitting a signal from said announcement link through a first established connection from said one register to said one trunk and back to said announcement link for establishing a second connection from said one trunk to a selected announcement circuit.

Claim 30

An announcement switching center in accordance with claim 24 wherein said announcement link comprises a single stage crossbar switch including hold magnets and said second connection establishing means comprises means for applying a ground connection through said first connection, said one register, and said one trunk to operate one of said select magnets.

Claim 31

An announcement switching center in accordance with claim 25 further comprising means responsive to said second connection through said switch for releasing said first connection.