JP2857652B2 - Private branch exchange - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a digital, such as ISDN office line
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a private branch exchange accommodating a plurality of office lines of a telephone line network as external lines , and particularly to a manual transfer and an automatic transfer thereof.

[0002]

2. Description of the Related Art Conventionally, in a manual transfer which can be performed by a private branch exchange (hereinafter, referred to as "PBX"), when a call is made between an outside line and an inside line, the call being transferred is transferred to another outside line by a manual transfer operation of an extension talker. In this case, after the outside line is temporarily put on hold, another outside line is captured, and then a call is made to a third party of the other outside line. Then, when a third party on the other external line answers, the hold of the external line is released, and the call to the internal line is disconnected, thereby realizing the manual transfer.

[0003] Conventionally, in an automatic transfer performed by the PBX, when an outside line automatic transfer is performed in which an incoming call is transferred from an outside line to another outside line without receiving a response when an incoming call is received from an outside line,
After the office line circuit, which is the office line interface, once answers the incoming call, it captures another outside line and then calls the talker to which the outside line is to be transferred. Then, automatic transfer is realized by connecting these two external lines via a PBX.

Generally, automatic transfer is used when a transfer destination is determined, and manual transfer is used regardless of whether a transfer destination is determined.

[0005]

However, in the above conventional example, when a call between an outside line and an extension is made to be transferred to another outside line by a manual transfer operation of an extension speaker, a time-division call is made. The use of two time slots on the road for transmitting and receiving signals and the occupation of two lines outside the capacity also have the disadvantage of reducing the traffic volume.

[0006] In addition, when an outside line automatic transfer is performed to transfer an incoming call to another outside line speaker without answering an incoming call from an outside line without answering, the two time slots of the time-division communication path are used for signal transmission. Used for transmission and reception, and
There is a disadvantage that the traffic is reduced due to the exclusive use of the line.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a private branch exchange which does not cause a decrease in traffic volume in manual transfer and automatic transfer to an outside line. .

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a private branch exchange that accommodates a plurality of office lines of a digital network as external lines and has a function of manually transferring to an external line . Each of the plurality of office lines to be accommodated is the digital circuit.
In the office line which can use the transfer service during communication provided by the line network
Originating storage means for storing whether, when communication between the first outside line and the extension, the destination of the external lines for transferring a call in communication by manual transfer operation in extension to external destination Control means for checking whether or not the first external line is a station line capable of using the transfer service during communication, wherein the control means includes a control unit for controlling whether the first external line is the transfer service during communication. In the case of a station line that can use the outside line, manual transfer to the transfer destination of the outside line is performed by using the transfer service during communication.

In addition, a plurality of office lines of a digital network
Accommodated as husband of the plurality of stations lines in a private branch exchange, accommodating with automatic transfer function inner line when a call arrives from the outside line to forward the incoming call to the destination of another outside line without response s
Storage means for storing whether or not the line is a station line which can use the call transfer service provided by the digital circuit network;
If you call the incoming call from the outside line to the destination of the in order to automatically transferred to the transfer destination external outside line, office line to the first outside line that has been set to automatic transfer is available the call forwarding service Control means for checking whether or not the call forwarding service is used. If the first external line for which the automatic transfer is set is a station line capable of using the call forwarding service, the control means uses the call forwarding service. By doing so, the outside line is automatically transferred to the transfer destination.

[0010]

In the private branch exchange according to the present invention, if the first outside line under communication is a station line which can use the transfer service during communication, manual transfer to the transfer destination of the outside line can be performed by using the transfer service during communication. Done.

If the first external line to which the automatic transfer is set is a station line that can use the call transfer service, the automatic transfer to the transfer destination of the external line is performed using the call transfer service.

[0012]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a PBX according to one embodiment of the present invention. This PBX has a configuration in which three ISDN office lines as a predetermined digital line network and three internal lines are accommodated. Has become.

In FIG. 1, 1 is a PBX body, 2, 3,
4 is an ISDN office line circuit for accommodating ISDN office lines IS1, IS2 and IS3, and 5, 6, and 7 are extensions IN1 and IN
2, an extension circuit for accommodating IN3; 8, a call path switch; 9, a call control process for setting, disconnecting, and restoring a call; and ISDN office line circuits 2, 3, 4, and an extension circuit 5 for performing manual transfer. , 6, 7 and a call control processing unit (control means) for controlling the communication path switch 8. 10 is a RAM (storage means), 11
Is a control bus, 12-1, 12-2, 12-3, 12-
4, 12-5 and 12-6 are time-division communication paths.

Next, an operation example of the PBX 1 shown in FIG. 1 will be described.

The ISDN central office line IS1 is an IDN provided by NTT.
This is an office line that has a contract to use the "Transferring Communication Service" of NS Net and can use the "Transferring Communication Service".
It is assumed that the ISDN office line IS2 is an office line that cannot use the service. In the PBX 1 shown in FIG. 1, when performing manual transfer, it can be classified into three types of manual transfer depending on the use form of the line. That is, (1) Manual transfer in which, for example, when one extension is busy with another extension, a speaker of one extension transfers a call in communication from one extension to another extension by a manual transfer operation.

(2) When an outside line and an extension are in a call, the call is transferred manually from the extension to another extension by a manual transfer operation by the extension talker. (3) The outside line and the extension are in a call. At this time, manual transfer is performed in which a call being communicated is transferred from the extension to another external line by a manual transfer operation by the extension talker.

In the present embodiment, the case (3) of manual transfer of an outside line will be described.

FIG. 2 is a flow chart for explaining the operation in the case where a call is being transferred between an extension and an extension while another extension is manually transferred from the extension to another extension. Hereinafter, description will be made with reference to this flowchart.

First, an incoming call is made to the ISDN office line IS1, which is an external line, and the office line IS1 is talking with the extension line IN1 (step S1). In order to call a third party speaker via the outside line and transfer the call in progress from the extension IN1 to the outside line of the third party, the speaker of the extension IN1 first performs a manual transfer operation (step S2). Then, a hold operation is performed (step S3), and a call is made to a third party speaker via an outside line (step S4).

Here, the call control processor 9 checks each ISDN station line to check whether the external line IS1 currently used is an ISDN station line that can use the "communication transfer service" of the INS network provided by NTT. "Transferring service during communication"
The contents of the RAM 10 in which the use or non-use of the service is registered are read, and the use or non-use of the "communication transfer service" is checked (step S5). ISDN office line IS currently used
1 can use the “transfer service during communication”, the call control processing unit 9 sends the ISDN office line IS1 to the ISDN office line circuit 2.
Is instructed to transmit and receive a signal in accordance with the procedure for activating the "transfer service during communication" via the INS network (step S6).

FIG. 3 is a signal sequence diagram of the "transfer service during communication" activation procedure. This activation procedure is described in the technical reference document "Interface of INS Net Service Volume 4 (Layer 3 Circuit Switching Additional Service)" issued by NTT. ) "
This is based on the protocol described in. In the figure, 1 is a PBX, 20 is an INS network, 30 is an outside line speaker, and 40 is a transfer destination speaker.

As shown in FIG. 3, the ISDN line circuit 2
(PBX1 in FIG. 3) and the transmission / reception of signals between the INS network 20 and the “transfer service during communication”
Is activated, the call is transferred within the INS network 20, and the call between the INS network 20 and the PBX 1 is released (step S7).

The ISDN office line circuit 2 is an INS network 2
From 0, the call transfer is completed and the first outside talker (office line IS
Upon receiving a notification that the call to the speaker (1) has been released, the call control processor 9 is notified via the control bus 11 that the transfer has been completed.

The call control processor 9 controls the call path switch 8 and the extension circuit 5 so as to terminate the call between the outside line speaker on the ISDN central office line IS1 and the speaker on the extension line IN1.

In this manner, external line manual transfer can be performed.

Next, a description will be given of a case where an external line is manually transferred from a state in which a call is received on the ISDN central office line IS2 which is an external line and a call is being made with the internal line IN1.

First, it is assumed that there is an incoming call on the ISDN office line IS2, and that the office line IS2 is talking with the extension IN1 (step S1). In order to call a third party speaker via the outside line and transfer the call in progress from the extension IN1 to the outside line of the third party, the speaker of the extension IN1 first performs a manual transfer operation in the same manner as described above. (Step S2), a hold operation is performed (step S3), and a call is made to a third party speaker via an outside line (step S4).

Here, the call control processing unit 9 checks whether the currently used outside line IS2 is an ISDN station line which can use the "transfer service during communication" of the INS network provided by NTT. Similarly, the contents of the RAM 10 in which the use of the “communication transfer service” is registered for each office line are read, and the use of the “communication transfer service” is checked (step S5).

Since the "transfer service during communication" is not available for the ISDN office line IS2, another ISDN office line (for example, the ISDN office line IS3) is acquired (step S).
8). Then, the call with the ISDN office line IS2 is put on hold, and a call is made to an external third party via the newly acquired ISDN office line. When a third party on the outside line answers, the hold on the ISDN central office line IS2 is released, and at the same time, the call with the extension IN1 is terminated, so that the ISDN via the PBX1 is terminated.
The outside line speaker of the local line IS2 and the newly captured ISDN
The call control processor 9 controls the call path switch 8 so that a call can be made with a third party outside the office line, and a time-division call between the ISDN office line IS2 and another ISDN office line. By making the connection on the road 12, a call can be made between the two speakers on the outside line, and the outside line can be manually transferred (step S9).

Next, another operation example of the PBX shown in FIG. 1 will be described. In other operation examples, the function of the call control processing unit 9 is different from that of the first operation example. In another operation example, the call control processing unit 9 has an automatic transfer function to an outside line. The automatic transfer and the manual transfer are performed, for example, by switching programs, and a switching command is issued by, for example, a dedicated telephone dedicated to the PBX1.

Next, another operation example will be described with reference to FIG.

In FIG. 1, the ISDN office line IS1 is NT
It is assumed that the subscriber line has a contract for using the “call transfer service” of the INS network provided by T and can use the “call transfer service”, and the ISDN line IS1 is a line that cannot use the service. In the PBX 1 shown in FIG. 1, when performing automatic transfer, it can be classified into three types according to the use form of the line. That is, (1) automatic transfer between extension lines, (3) automatic transfer between extension lines and outside lines, and (3) automatic transfer between outside lines and outside lines.

In this operation example, the case of (3) automatic transfer of an outside line will be described. FIG. 4 is a flowchart illustrating this operation example. Hereinafter, description will be made with reference to this flowchart. First, it is assumed that there is an incoming call to the ISDN office line IS1, which is an external line, and that the automatic transfer is set for this ISDN office line IS1 (step S11). ISDN office line circuit 2
Notifies the call control processor 9 via the control bus 11 that there is an incoming call to an outside line for which automatic transfer is set. Here, the call control processing unit 9 checks whether the ISDN office line IS1 is an ISDN office line that can use the “end transfer service” of the INS network provided by NTT.
The contents of the RAM 10 in which the use of the "call transfer service" is registered is read for each N station lines, and the use of the "call transfer service" is checked (step S12). Here, since the ISDN office line IS1 can use the “call transfer service”, the call control processing unit 9
IN using the ISDN office line IS1 for the SDN office line circuit 2.
Instruct the S-net to transmit and receive signals in accordance with the procedure for activating the "call transfer service" (step S1).
3).

FIG. 5 is a signal sequence diagram of this "call transfer service" activation procedure. This activation procedure is described in the technical reference document "Interface of INS Net Service Volume 4 (Layer 3 Circuit Switching Additional Service)" issued by NTT. ”According to the protocol described in In the figure, the same or corresponding parts as those in FIG. 3 are denoted by the same reference numerals.

As shown in FIG. 5, the ISDN line circuit 2
(PBX1 in FIG. 5) and the transmission and reception of signals between the INS network 20 and the “call transfer service” are activated, the call between the INS network 20 and the PBX1 is released, and the INS network 20 is released. The call is transferred within (step S14). As a result, the outside line is automatically transferred (step S15).

Next, a case where a call arrives at the ISDN central office line IS2, which is an external line for which automatic transfer is set, will be described (step 11). The ISDN line circuit 2 is connected to the control bus 11
, The call control processing unit 9 is notified that there is an incoming call to an outside line for which automatic transfer is set. In this case, the call control processing unit 9 similarly checks the “call transfer information” for each ISDN station line in order to check whether the ISDN station line 1 is an ISDN station line that can use the “call transfer service” of the INS network provided by NTT. RAM in which availability of "service" is registered
Then, the content of No. 10 is read, and it is checked whether or not the "call transfer service" can be used (step S12). ISDN office line IS2
Since the "call forwarding service" is not available, the call control processor 9 instructs the ISDN central office circuit 2 to respond to the incoming call via the control bus 11 (step SS1).
6). And another ISDN line (for example, ISD
N station line IS3) is captured (step S17).

Next, a call is made to the speaker on the outside line of the transfer destination via the newly captured ISDN office line (step S18).
When the outside line speaker of the transfer destination answers (step S9), P
The call control processor 9 controls the call path switch 8 so that a call can be made between the outside line speaker of the ISDN office line IS2 and the outside line speaker to which the newly acquired ISDN office line is transferred via the BX1. Control the ISDN office line IS2 and another IS
By connecting to the DN line via the time-division communication path 12 (step S20), a call can be made between the two external speakers, and the external line transfer is completed (step S2).
1) The outside line is automatically transferred.

In FIG. 1, the number of ISDN office lines and the number of extensions are each three, but the number does not have to be three. Further, the storage means for storing whether or not the accommodated ISDN station line can use the “communication transfer service” or the “call transfer service” of the INS network provided by NTT is a RAM. Other storage means such as a memory may be used. Further, the call control processing unit is a means for checking whether or not the external line for which automatic transfer is set is an ISDN station line that can use the "transfer service during communication" or the "call transfer service". Means may be used.

[0040]

As described above, the present invention provides a digital
In a private branch exchange that accommodates a plurality of office lines of a circuit network as external lines and has a function of manually transferring to an external line , a plurality of
Storage means for storing whether or not each of the office lines is an office line which can use a transfer service during communication provided by the digital circuit network , and manual transfer at the extension during communication between the first outside line and the inside line In order to transfer a call being communicated to an external line transfer destination by an operation, the first call is transmitted to the external line transfer destination.
Control means for checking whether or not the outside line is a station line capable of using the transfer service during communication, and the control means,
The first outside line can use the call transfer service.
In the case of the office line, since the manual transfer to the transfer destination of the outside line is performed by using the transfer service during communication,
If the line is available for medium transfer service, transfer during communication
By using the service, the outside
After the transfer is performed, the line is temporarily released and
To enable the line to be used for other purposes.
Both are office lines where transfer service during communication cannot be used.
If you cannot use the call transfer service,
Requesting the transfer service during communication from the digital network
Unnecessary useless operation can be prevented.

In addition, a plurality of office lines of the digital circuit
Accommodated as husband of the plurality of stations lines in a private branch exchange, accommodating with automatic transfer function inner line when a call arrives from the outside line to forward the incoming call to the destination of another outside line without response s
Storage means for storing whether or not the line is a station line which can use the call transfer service provided by the digital circuit network;
If you call the incoming call from the outside line to the destination of the in order to automatically transferred to the transfer destination external outside line, office line to the first outside line that has been set to automatic transfer is available the call forwarding service Control means for checking whether or not the call forwarding service is used. If the first external line for which the automatic transfer is set is a station line capable of using the call forwarding service, the control means uses the call forwarding service. Automatically transfer to the transfer destination of the outside line, so that the call transfer service can be used.
If it is an office line, use the call forwarding service
Automatic transfer to the transfer destination of the outside line was performed and the transfer was performed
After that, release the office line and use the office line for other purposes
And use call forwarding services
Call forwarding service is not available for office lines that cannot
Despite the lack of a call transfer service
Useless operation that requires a service can be prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a PBX according to the present invention.

FIG. 2 is a flowchart showing a first operation example of the PBX of FIG. 1;

FIG. 3 is a sequence diagram illustrating a “transfer service during communication” activation procedure in the first operation example of the PBX in FIG. 1;

FIG. 4 is a flowchart showing a second operation example of the PBX of FIG. 1;

FIG. 5 is a sequence diagram showing a “call transfer service” activation procedure in the second operation example of the PBX of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PBX 2,3,4 ISDN office line circuit 5,6,7 Extension circuit 8 Communication path switch 9 Call control processing part 10 RAM 11 Control bus 12-1 Time division communication path 12-2 Time division communication path 12-3 Split channel 12-4 Time-division channel 12-5 Time-division channel 12-6 Time-division channel IS1, IS2, IS3 ISDN office line IN1, IN2, IN3 Extension

Continuation of front page (56) References JP-A-2-32660 (JP, A) JP-A-62-295550 (JP, A) JP-A-2-16857 (JP, A) JP-A-2-260749 (JP, A) JP-A-3-121698 (JP, A) JP-A-4-290055 (JP, A) JP-A-4-233364 (JP, A) JP-A-4-270541 (JP, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) H04M 3/00 H04M 3/16-3/20 H04M 3/38-3/58 H04M 7/00-7/16 H04Q 3/58-3/62

Claims (4)

(57) [Claims] 1. A digital circuit network comprising a plurality of office lines and an outside line.
Containing Te, the private branch exchange having a manual transfer function to the external line, each of a plurality of said office line to accommodate people of the digital network
Storage means for storing whether or not the line is available for use during the communication transfer service to be provided; and, during communication between the first outside line and the inside line, the call being communicated by the manual transfer operation on the inside line is transferred to the outside line. Control means for checking whether or not the first external line is a station line that can use the transfer service during communication when a call is made to the transfer destination of the external line to transfer to the external line. The private branch exchange, wherein if the first external line is a station line that can use the transfer-during-communication service, manual transfer to the transfer destination of the external line is performed by using the transfer-during-communication service. 2. If the first outside line is a station line that cannot use the transfer service during communication, the second outside line is captured, and a call destination of the outside line is called via the second outside line. using said first and second outside line by private branch exchange according to claim 1, characterized by manually transferring a call in a communication to the destination of the outside line. 3. The digital line network has a plurality of office lines and external lines.
Containing Te, the private branch exchange having a call forwarding feature to forward the incoming call to the inner line does not respond to the destination of another outside line when the call from the outside line, a plurality of each said digital line of the station line to accommodate Mesh
Storage means for storing whether the office line available call forwarding service provided, call the incoming call from the first outside line to the destination of the outside line in order to automatically transferred to the transfer destination external Control means for checking whether or not the first outside line for which automatic transfer is set is a station line which can use the call transfer service, wherein the control means sets the automatic transfer. A private branch exchange, wherein if the first external line is a local line that can use the call transfer service, the call is automatically transferred to a transfer destination of the external line by using the call transfer service. 4. When the first outside line for which automatic transfer is set is a station line in which the call transfer service cannot be used ,
Capturing the second outside line, by calling the destination of the outside line via the second outside line, using the first and second outside line, automatic incoming call to the destination of the outside line private branch exchange according to claim 3, wherein the this <br/> forwarding.