Path finding system for multi-stage switching matrix

Claim 2

In a common control telephone system, a path checking and selecting arrangement for establishing a path through a multistage switching matrix from a selected input to an available one of a plurality of connection circuits comprising path selection means for detecting all paths available from said selected input to an intermediate point of said matrix, and allotting means responsive to said path selection means for selecting an available connection circuit associated with an output of the matrix capable of completing one of the available paths detected by said path selection means.

Claim 3

A system as defined in claim 1, wherein said connection circuits at least include junctors, trunks and registers, said allotting means including control means associated with respective groups of matrix outputs for detecting the simultaneous availability of a junctor and register or a trunk associated with a group of matrix outputs to which at least one available path determined by said path selection means is extendable.

Claim 4

A system as defined in claim 2, wherein said matrix includes three stages of switches each having a plurality of inputs connectable to any one of a plurality of outputs, said path selection means including a respective path selector connecting the outputs of each first stage switch to an input of each second stage switch for allowing the passage of scanning signals therebetween and a respective path detector connected to each of the inputs of a respective one of each third stage switch for detecting scanning signals passed by said path selectors.

Claim 5

A system as defined in claim 3, wherein said control means includes a plurality of control circuits, each control circuit monitoring the availability of the connection circuits associated with the outputs of a single respective third stage switch, a respectivE one of each of said path selectors being connected to a respective one of said control circuits, and common control means responsive to detection of a free control circuit and indication of an output of a path selector in a given control circuit for marking the output of the third stage switch associated with said free control circuit thereby establishing a path through the matrix thereto from said selected input.

Claim 6

A system as defined in claim 3, wherein each path through said matrix includes at least a mark lead for determining the availability of each part of the path between stages and a sleeve lead for holding a completed path once acquired by connection of ground thereto, said path selection means including circuit means responsive to the presence of a ground on the sleeve lead of a path for preventing passage of a scanning signal on the mark lead thereof.

Claim 7

A system as defined in claim 5, wherein said path detectors include blocking means responsive to the presence of a ground on the sleeve lead of a path for preventing passage of a scanning signal from the mark lead therethrough.

Claim 8

In a common control telephone system including a plurality of communication stations, a multi-stage switching matrix providing a plurality of paths from a selected input to each output thereof, a plurality of connection circuits in the form of junctors for interconnecting selected stations through said matrix and trunk circuits for establishing through said matrix outgoing connections from a selected station, and common control means including a plurality of registers for controlling the functioning of said connection circuits, a path checking and selecting arrangement for establishing a path through said matrix from a selected input to an available one of a plurality of connection circuits, comprising line control means for marking a single selected input of said matrix to which a station requesting service is connected, path selection means for extending said mark from said selected input on all available paths through said matrix, path detection means connected in said matrix prior to the last stage thereof for generating a control signal in response to detection of the extending mark, and allotting means responsive to receipt of a control signal for selecting an available connection circuit associated with an output of the matrix capable of completing one of the available paths detected by said path selection means.

Claim 9

In a common control telephone system including a plurality of communication stations, a multi-stage switching matrix providing a plurality of paths from a selected input to each output thereof, a plurality of connection circuits in the form of junctors for interconnecting selected stations through said matrix and trunk circuits for establishing through said matrix outgoing connections from a selected station, and common control means including a plurality of registers for controlling the functioning of said connection circuits, a path checking and selecting arrangement for establishing a path through said matrix from a selected input to an available one of a plurality of connection circuits, comprising line control means for marking a single selected input of said matrix to which a station requesting service is connected, path selection means for extending said mark from said selected input on all available paths through said matrix, path detection means connected in said matrix prior to the last stage thereof for generating a control signal in response to detection of the extending mark, and allotting means responsive to receipt of a control signal for selecting an available connection circuit associated with an output of the matrix capable of completing one of the available paths detected by said path selection means.

Claim 10

A system as defined in claim 7, wherein said matrix includes three stages, each stage of said matrix including a plurality of switches, each capable of connecting each switch input to any output of the same switch, each input of a first stage switch being connected to a respective station and each output thereof being connected to a respective input of each second stage switch, each output of a second stage switch being connected to a respective input of each third stage switch, the outputs of which are each connected to a respective connection circuit.

Claim 11

A system as defined in claim 8, wherein each path through said matrix includes at least an availability lead for determining the availability of each portion of the path between stages and a holding lead for holding a completed path once acquired by connection of ground thereto, said path selection means including a path selector connected to the holding leads at the output of each first stage switch for enabling the associated availability leads individually and in sequence only when no ground is detected on the associated holding lead.

Claim 12

A system as defined in claim 9, wherein each path selector includes a plurality of relays, each relay having contacts in a respective one of said availability leads at the output of a first stage switch, and scanning means for sequentially actuating said relays so as to complete the connection through the associated availability lead, and means connecting said relays to the associated holding leads so as to prevent actuation thereof by said scannIng means when a ground is present thereon.

Claim 13

A system as defined in claim 10, wherein each path selector is connected to said line control means for actuation exclusive of the other path selectors to permit scanning of the outputs of a single first stage switch to which said station requesting service is connected.

Claim 14

A system as defined in claim 10, wherein said path detection means includes a respective path detector connected to the inputs of each third stage switch between each of said availability and holding leads so as to pass the mark extending from the selected input of the matrix as said control signal when at least one path to the respective switch has a holding lead free of ground connection.

Claim 15

A system as defined in claim 12, wherein said allotting means includes a control circuit associated with the group of connection circuits connected to each respective third stage switch, each control circuit including means for monitoring the availability of said connection circuits and stop scan means responsive to receipt of a control signal from the path detector connected thereto and the availability of at least one connection circuit in the associated group for stopping said scanning means.

Claim 16

A system as defined in claim 13, wherein said common control means includes connection circuit scanning means for scanning the availability of individual connection circuits in the respective groups associated with said control circuits and additional stop scan means in each control circuit for stopping said circuit scanning means in response to detection of a single available connection circuit in the selected group.

Claim 17

A system as defined in claim 12, wherein each path detector includes a detection circuit connected to each input of the third stage switch having a first diode connected between said holding lead and a switching point, a second diode connected between an output of the detection circuit and said switching point with opposite polarity to said first diode and a connection between said availability lead and said switching point.

Claim 18

A system as defined in claim 7, wherein each path through said matrix includes at least an availability lead for determining the availability of each portion of the path between stages and a holding lead for holding a completed path once acquired by connection of ground thereto, said path selection means including a path selector connected to the holding leads at the output of each first stage switch for enabling the associated availability leads individually and in sequence only when no ground is detected on the associated holding lead.

Claim 19

A system as defined in claim 16, wherein each path selector includes a plurality of relays, each relay having contacts in a respective one of said availability leads at the output of a first stage switch, and scanning means for sequentially actuating said relays so as to complete the connection through the associated availability lead, and means connecting said relays to the associated holding leads so as to prevent actuation thereof by said scanning means when a ground is present thereon.

Claim 20

In a common control telephone system including a multi-stage switching matrix having a plurality of matrix switches provided with a plurality of interconnectable switch inputs and switch outputs in each stage and links between stages connecting respective switch outputs of one stage to respective switch inputs of an adjacent stage, a path checking and selecting arrangement for establishing a path through said multi-stage switching matrix from a selected matrix input to an available matrix output, comprising line control means for marking said selected matrix input with a potential, path selection means responsive to said line control means for sequentially enabling only selected outputs of the matrix switch whose input is marked with a potential, and path detection means connected to the inputs of the matrix switches in the last stage of said multi-stage switching matrix For disabling said scanning means in response to detection of said mark potential only at selected inputs of one of said last stage switches.

Claim 21

In a common control telephone system including a multi-stage switching matrix having a plurality of matrix switches provided with a plurality of interconnectable switch inputs and switch outputs in each stage and links between stages connecting respective switch outputs of one stage to respective switch inputs of an adjacent stage, a path checking and selecting arrangement for establishing a path through said multi-stage switching matrix from a selected matrix input to an available matrix output, comprising line control means for marking said selected matrix input with a potential, path selection means responsive to said line control means for sequentially enabling only selected outputs of the matrix switch whose input is marked with a potential, and path detection means connected to the inputs of the matrix switches in the last stage of said multi-stage switching matrix For disabling said scanning means in response to detection of said mark potential only at selected inputs of one of said last stage switches.

Claim 22

A system as defined in claim 18, wherein said matrix includes three stages, each stage of said matrix including a plurality of switches connecting each input thereof to all of the outputs thereof, each input of a first stage switch forming a matrix input and each output thereof being connected to a respective input of each second stage switch, each output of a second stage switch being connected to a respective input of each third stage switch.

Claim 23

A system as defined in claim 18, wherein each path through said matrix includes at least an availability lead for determining the availability of each portion of the path between stages and a holding lead for holding a completed path once acquired by connection of ground thereto, said path selection means including a path selector connected to the holding leads at the output of each first stage switch for enabling the associated availability leads individually and in sequence only when no ground is detected on the associated holding lead.

Claim 24

A system as defined in claim 20, wherein each path selector includes a plurality of relays, each relay having contacts in a respective one of said availability leads at the output of a first stage switch, and scanning means for sequentially actuating said relays so as to complete the connection through the associated availability lead, and means connecting said relays to the associated holding leads so as to prevent actuation thereof by said scanning means when a ground is present thereon.

Claim 25

A system as defined in claim 21, wherein each path selector is connected to said line control means for actuation exclusive of the other path selectors to permit scanning of the outputs of a single first stage switch to which said station requesting service is connected.

Claim 26

A system as defined in claim 22, wherein said path detection means includes a respective path detector connected to the inputs of each third stage switch between each of said availability and holding leads so as to pass the mark extending from the selected input of the matrix as said control signal when at least one path to the respective switch has a holding lead free of ground connection.

Claim 27

A system as defined in claim 23, wherein each path detector includes a detection circuit connected to each input of a third stage switch having a first diode connected between said holding lead and a switching point, a second diode connected between an output of the detection circuit and said switching point with opposite polarity to said first diode and a connection between said availability lead and said switching point.

Claim 28

In a common control telephone system, a path checking and selecting arrangement for establishing a path through a three-stage switching matrix from a voltage marked input to an available output comprising path scanning means for enabling only those portions of paths between said marked input and the second stage of said three-stage matrix which are available for use, and path detecting means for detecting only on those portions of paths between the second and third stages of said three-stage matrix the voltage from said marked input.

Claim 29

In a common control telephone system, a path checking and selecting arrangement for establishing a path through a three-stage switching matrix from a voltage marked input to an available output comprising path scanning means for enabling only those portions of paths between said marked input and the second stage of said three-stage matrix which are available for use, and path detecting means for detecting only on those portions of paths between the second and third stages of said three-stage matrix the voltage from said marked input.

Claim 30

A system as defined in claim 25, wherein said path scanning means includes individual relays each having contacts in a respective one of the paths between said marked input and the second stage of said three-stage matrix, means for sequentially enabling said individual relays and means responsive to detection of the busy condition of a path between the first and second stages of said three-stage matrix for blocking the enabling of individual relay having contacts in this path.

Claim 31

A system as defined in claim 26, wherein said path detecting means includes detection circuits connected to those portions of paths between the second and third stages of said three-stage matrix, each detection circuit having diodE means responsive to a voltage indicating the busy condition of a respective path portion between the second and third stages for blocking passage of the voltage mark from said marked input.

Claim 32

A system as defined in claim 27, further including a plurality of connection circuits for selective connection to an output of said matrix and allotting means for selecting an available connection circuit associated with an output of the matrix capable of completing one of the available paths detected by said path detecting means.

Claim 33

A system as defined in claim 28, wherein said allotting means includes coincidence means responsive to the simultaneous indication of availability of a connection circuit associated with a path connected to a detection circuit capable of passing the voltage mark from the marked input for disabling said means for sequentially enabling said individual relays.

Claim 34

A system as defined in claim 28, wherein said connection circuits at least include junctors, trunks and registers, said allotting means including control means associated with respective groups of matrix outputs for detecting the simultaneous availability of a junctor and register or a trunk associated with a group of matrix outputs to which at least one available path determined by said path selection means is extendable.