Crosspoint network path finding system

Claim 2

A path finding system for effecting selection and interconnection of devices through a switching network, wherein said network includes a plurality of switching matrix stages interconnected to provide plural paths between devices connected to opposite ends of said network, and wherein each stage is divided into separate matrix groups, said path finding system comprising: means for selectively marking devices connected to matrix groups in the stages on opposite ends of the network; switching means in the plurality of matrix groups in a stage at one end of the network for providing signals designating the busy-free condition of individual interconnections between these matrix groups and the matrix groups of an adjacent stage; means for sequentially detecting the busy-free condition of the individual interconnections between a matrix group in said end stage connected to a marked device and the matrix groups of the adjacent stage, and circuit means responsive to a detected free condition in one of said interconnections for enabling the interconnection to complete a path through said network between marked devices connected to opposite ends of said network.

Claim 3

A path finding system as defined in claim 1 wherein: said circuit means responsive to a detected free condition includes switch means connected in series with individual ones of said interconnections, means for sequentially applying enabling signals, synchronized to said detecting means, to the switch means connected in series with the interconnections to the matrix group connected to a marked device at a rate wherein the switch means do not respond to said signal, and means for stopping said means for applying the enabling signals when a free path is detected for applying an enabling signal for a sufficient period of time to complete a path between marked devices on opposite ends of said network.

Claim 4

A path finding system for effecting selection and interconnection of devices through a switching network, wherein said network includes a plurality of switching matrix stages interconnected to provide plural control paths and corresponding plural switch paths between devices connected to opposite ends of said network, wherein each stage is divided into a plurality of separate matrix groups, and wherein each matrix group includes a plurality of cross-point switching devices arranged to form a matrix switch with the cross-point devices connected in said control paths and their switches connected in said switch paths, said path finding system comprising: means for selectively marking the control path connections of the devices at opposite ends of the network; switching means in the plurality of matrix groups in a stage at one end of the network for providing signals designating the busy-free condition of control path interconnections between the matrix groups and the matrix groups in an adjacent stage; scanning means for sequentially enabling individual control path interconnections between a matrix group of said end stage that is connected to a marked device and the matrix groups of an adjacent stage, wherein said control path interconnections are enabled for a time duration that is insufficient to switch the cross-point devices, and means for detecting a signal indicating a free control path interconnection has been enabled, and for stopping said scanning means so that said scanning means applies a signal of sufficient duration to switch connected cross-point devices to complete a control path and a corresponding switch path through the network between marked devices.

Claim 5

A path finding system for effecting selection and interconnection of devices through a switching network, wherein said network includes a plurality of switching matrix stages interconnected to provide plural control paths and corresponding plural switch paths between devices connected to opposite ends of said network, wherein each stage is divided into a plurality of separate matrix groups, and wherein each matrix group includes a plurality of cross-point switching devices arranged to form a matrix switch with the cross-point devices connected in said control paths and their switches connected in said switch paths, said path finding system comprising: means for selectively marking the control path connections of the devices at opposite ends of the network; switching means in the plurality of matrix groups in a stage at one end of the network for providing signals designating the busy-free condition of control path interconnections between the matrix groups and the matrix groups in an adjacent stage; scanning means for sequentially enabling individual control path interconnections between a matrix group of said end stage that is connected to a marked device and the matrix groups of an adjacent stage, wherein said control path interconnections are enabled for a time duration that is insufficient to switch the cross-point devices, and means for detecting a signal indicating a free control path interconnection has been enabled, and for stopping said scanning means so that said scanning means applies a signal of sufficient duration to switch connected cross-point devices to complete a control path and a corresponding switch path through the network between marked devices.

Claim 6

A path finding system as defined in claim 3 including: means for detecting the completion of a connection through the network, and means for restarting said scanning means if a connection through said network is not completed within a preset period of time after said scanning means is stopped.

Claim 7

A path finding system as defined in claim 4 wherein said scanninG means includes: separate enabling circuits for each of said control path interconnections in each of said matrix groups in said end stage, and wherein the enabling circuits are connected in series with their respective control path interconnections; a source of sequential scanning signals having time durations insufficient to switch said enabling circuits, and control means including a switching circuit for completing the connections between said source and said enabling circuits for sequentially applying the scanning signals to the enabling circuits of a matrix group connected to a marked device.

Claim 8

A path finding system for effecting selection and interconnection of telephone circuits through a switching network wherein said network includes a plurality of switching matrix stages, wherein each stage is divided into separate matrix groups, wherein each matrix group includes a plurality of cross-point devices arranged to form a matrix switch, and wherein the cross-point devices in the matrix groups are interconnected between matrix groups of adjacent stages by control leads for controlling the actuation of said cross-point devices to provide plural paths between telephone circuits connected to opposite ends of said network, said path finding system comprising: means for selectively marking the control leads of telephone circuits connected to matrix groups in the stages on opposite ends of said network; switch means in the plurality of matrix groups in an end stage for providing signals designating the busy-free condition of the control lead interconnections between the matrix groups in said end stage and the matrix groups of an adjacent stage; scanning means for sequentially enabling the control lead interconnections between a matrix group in said end stage connected to one of said marked telephone circuits and the matrix groups of the adjacent stage, and wherein the time duration the control lead interconnections are enabled is insufficient to switch the cross-point devices; switching means connected in the control lead interconnections between the matrix groups in the other end stage and its adjacent stage for disabling the control lead interconnections therebetween corresponding to busy paths; means for detecting a signal indicating a free condition in control lead interconnection in the scanned matrix group and for stopping said scanning means so that the free control lead interconnection is enabled for a sufficient duration to switch cross-point devices in said plurality of stages to complete the control path between marked telephone circuits on opposite ends of said network; means for detecting the completion of a connection between marked telephone circuits at opposite ends of the network, and means for restarting the scanning means if a connection through said network between the marked telephone circuits is not completed within a preset period of time after said scanning means is stopped.

Claim 9

A path finding system for effecting selection and interconnection of telephone circuits through a switching network wherein said network includes a plurality of switching matrix stages, wherein each stage is divided into separate matrix groups, wherein each matrix group includes a plurality of cross-point devices arranged to form a matrix switch, and wherein the cross-point devices in the matrix groups are interconnected between matrix groups of adjacent stages by control leads for controlling the actuation of said cross-point devices to provide plural paths between telephone circuits connected to opposite ends of said network, said path finding system comprising: means for selectively marking the control leads of telephone circuits connected to matrix groups in the stages on opposite ends of said network; switch means in the plurality of matrix groups in an end stage for providing signals designating the busy-free condition of the control lead interconnections between the matrix groups in said end stage and the matrix groups of an adjacent stage; scanning means for sequentially enabling the control lead interconnections between a matrix group in said end stage connected to one of said marked telephone circuits and the matrix groups of the adjacent stage, and wherein the time duration the control lead interconnections are enabled is insufficient to switch the cross-point devices; switching means connected in the control lead interconnections between the matrix groups in the other end stage and its adjacent stage for disabling the control lead interconnections therebetween corresponding to busy paths; means for detecting a signal indicating a free condition in control lead interconnection in the scanned matrix group and for stopping said scanning means so that the free control lead interconnection is enabled for a sufficient duration to switch cross-point devices in said plurality of stages to complete the control path between marked telephone circuits on opposite ends of said network; means for detecting the completion of a connection between marked telephone circuits at opposite ends of the network, and means for restarting the scanning means if a connection through said network between the marked telephone circuits is not completed within a preset period of time after said scanning means is stopped.

Claim 10

A path finding system as defined in claim 6 wherein: said cross-point device comprises relay switches having mark and sleeve relay coils, wherein the mark coils are interconnected by said control leads, wherein said sleeve coils are interconnected by sleeve leads and by contacts of their respective relay switches to form plural holding current paths, and wherein contacts of said relay switches are interconnected to form plural signal paths, and said switch means comprises a separate contact from each of said relay switches in each of said scanned matrix groups in said end stage wherein the contacts are interconnected in said matrix groups to provide a separate busy-free signal for each of the control lead interconnections to said scanned matrix groups and so that when one of the relays connected to a control lead interconnection is activated the contacts of the activated relay provide a busy signal for that control lead interconnection.