JPS643107B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to connection control between a plurality of exchanges connected by dedicated lines, and in particular, to control connections between an extension line and an outside line accommodated in one exchange This invention relates to an inter-exchange connection system that enables transfer connections to extensions accommodated in exchanges.

(b) Background of the technology In an automatic private branch exchange, an extension that is currently talking to an outside line, such as a central office line, temporarily puts the call on hold and calls another extension, and then resumes calling after the other extension answers. An automatic transfer function that transfers calls to other extensions is widely used. On the other hand, as the number of extensions increases, or when switching equipment is distributed, a new switching equipment interconnected with the existing switching equipment via dedicated lines may be installed to accommodate the extensions in a distributed manner.

(c) Prior Art and Problems FIG. 1 is a diagram showing an example of a conventional transfer control method in this type of private branch exchange. In Figure 1, the private branch exchange consists of two sets of exchanges EX1 and EX2.
The exchange EX1 has extensions A and B.
, central office line L1, and dedicated line L3 leading to exchange EX2.
is accommodated, and the exchange EX2 has extension C and
A central office line L2 and a dedicated line L3 leading to the exchange EX1 are accommodated. Exchange EX1 call path switch
On the extension accommodating terminal side of SW1, there are extension circuits LC1 and LC2 that accommodate extensions A and B, and a dedicated line L.
The incoming call connection terminal of the leased line trunk LDT1 accommodating the office line L1 is connected to the incoming call connection terminal of the leased line trunk LDT1 accommodating the office line L1, and the office line trunk COT1 accommodating the office line L1 and the outgoing call connection terminal of the leased line trunk LDT1 are connected to the outside line accommodating terminal side. Furthermore, the incoming connection terminal of the dedicated line trunk LDT2 that accommodates the dedicated line L3 and the extension circuit LC3 that accommodates the extension C are connected to the extension accommodating terminal side of the call path switch SW2 of the exchange EX2, and the external line accommodating terminal side is a central office line trunk that accommodates central office line L2.
COT2 and the outgoing connection terminal of leased line trunk LDT2 are connected. The call path switch SW1 switches between extension A and central line L under the control of the central controller CC1.
1. Connect extension A and dedicated line L3, as well as extensions A and B. Similarly, the communication path switch SW2 connects the extension C and the office line L2, the extension C and the private line L3, and the extensions together under the control of the central controller CC2. Assume that extension A and office line L1 are currently talking. In this state, after extension A performs a predetermined hold operation to transfer the call to office line L1 to extension B,
Next, when extension A selects extension B's phone number,
The central controller CC1 calls extension B, and when extension B answers, connects extensions A and B. When extension A requests extension B to make a call to office line L1 and is restored, the call between extension A and office line L1 is transferred to extension B.

On the other hand, extension A, which is talking to central office line L1, is at exchange EX2.
If you request a transfer to extension C accommodated in the office line, and after performing the hold operation as described above, select the number for the dedicated line L3, the central controller CC1 transfers the call from the office line trunk COT1 to the office line L1. After transmitting the sound, connect the extension accommodation terminal A in which extension A of the communication path switch SW1 is accommodated to the dedicated line trunk LDT.
1 is connected to the outside line accommodating terminal C which accommodates the outgoing connection terminal C, and the dedicated line trunk LDT1 is set to the outgoing connection state. On the other hand, in the exchange EX2, the leased line trunk LDT2 is activated via the leased line L3 and becomes connected to an incoming call. Next, when extension A selects the telephone number of extension C, the telephone number information is transferred to leased line trunk LDT1 and leased line L3.
and is transmitted to the central controller CC2 via the leased line trunk LDT2. The central control unit CC2, which received the telephone number of extension C, calls extension C.
When the extension C responds, the communication path switch SW2 connects the extension receiving terminals N and H in which the incoming call connection terminals of the extension C and the dedicated line trunk LDT2 are accommodated. As a result of the above, extension A is connected to the extension circuit LC1, the extension accommodating terminal A of the call path switch SW1, the external line accommodating terminal C, the outgoing connection terminal of the leased line trunk LDT1,
Leased line trunk LDT1 in outgoing connection state, leased line L3 in outgoing connection state, leased line trunk in incoming connection state
It is connected to the extension C via the LDT 2, the incoming call connection terminal of the leased line trunk LDT 2', the extension receiving terminals E and D of the communication path switch SW2, and the extension circuit LC3. However, even if extension A requests extension C to make a call to central office line L1 and the call is restored, central control unit CC1
does not have the function of connecting the outside line receiving terminals to the communication path switch SW1. In other words, in a relatively small-scale private branch exchange, incoming calls from a leased line are handled in the same way as internal line interconnection, and outgoing calls to the leased line are handled in the same way as outgoing connections from an extension line to an external line, thereby improving the connection control function of the central controller. If this is simplified, incoming calls from the central office line cannot be connected to other exchanges via the dedicated line.

As is clear from the above explanation, in a conventional transfer control system, although extension A can automatically transfer a call to the central office line L1 to another extension B accommodated in the same exchange EX1, the private line L3 Extension C accommodated in another exchange EX2 connected by
It was impossible to make a transfer connection.

(d) Purpose of the Invention The purpose of the present invention is to eliminate the drawbacks of the conventional transfer control system as described above, and to make it possible to transfer calls to outside lines to extensions accommodated in other exchanges connected by dedicated lines. It is in doing.

(e) Structure of the Invention In the present invention, after the first extension line that is in use with an outside line in the first exchange performs a predetermined hold operation, When a second extension is called, the first exchange is connected via the leased line and the external line accommodation terminal until the second extension answers, and the second exchange is connected via the leased line and the extension line accommodation terminal. However, when the second extension responds, the first exchange performs connection switching via the dedicated line and the extension accommodating terminal, and the second exchange changes the connection via the dedicated line and the external line accommodating terminal. As a result, the first exchange can connect the outside line accommodated at the outside line accommodation end and the dedicated line connected to the extension line accommodation terminal, allowing calls between the outside line accommodated in the first exchange and the extension line,
It becomes possible to transfer the information to an extension housed in the second exchange via the dedicated line.

(f) Embodiment of the invention An embodiment of the invention will be described below with reference to the drawings. 2 and 3 are diagrams for explaining an inter-exchange connection system according to an embodiment of the present invention, FIGS. 4A and 4B are diagrams for explaining the switching control function in the originating exchange, and FIG. A and B are diagrams illustrating the switching control function in the destination exchange, and FIG. 6 is a diagram showing the detailed configuration of the exchange according to an embodiment of the present invention. Note that the same reference numerals indicate the same objects throughout the figures. In Figures 2 and 3, the central control unit in one of the exchanges EX1
CC1' is provided with a switching control function XT1, and the central control unit CC2' in the other exchange EX2 is provided with a switching control function XT2. As mentioned above, FIG. 2 shows that extension A holds the incoming call from central office line L1, receives the call to extension C via leased line trunk LDT1, leased line L3, and leased line trunk LDT2, and shows that the call is in progress. It shows. Here, if extension C responds to the call as shown in FIG. 1, if extension accommodating terminals N and E of switch SW2 are connected, connection will not be possible after extension A is restored. Therefore, as shown in FIG. 3, the present invention switches the changeover switch r2 in the dedicated line trunk LDT2 when the other party's extension responds, connects the extension C to the dedicated line L2 as if it were a call, and on the EX1 side, the extension C When the central control unit CC1' confirms the response, it switches the changeover switch r1 in the leased line trunk LDT1 and opens the communication path between extension accommodation terminal A and outside line accommodation terminal C. , and change the connection to extension A as if the call were received from dedicated line L1. In this way, when extension A is restored,
The communication path between extension line accommodation terminal RO and outside line accommodation terminal G can be connected. Switching control function in the above
The processing steps for XT1 and XT2 are shown in FIGS. 4A and B and FIGS. 5A and B. Next, one embodiment of the present invention will be concretely connected with reference to FIG. In Figure 6, the private branch exchange also consists of two sets of exchanges.
It is composed of EX1 and EX2, and the exchange EX1 has extensions A and B, the central office line L1, and the exchange EX2.
It accommodates the dedicated line L3 leading to the exchange EX
2 accommodates an extension C, a central office line L2, and a dedicated line L3 leading to the exchange EX1. Exchange EX1
Extension accommodation terminals E1 to E of the communication path switch SW
3 has an extension circuit LC accommodating extensions A and B.
1 and LC2 are connected to the incoming call connection terminal IC1 of the leased line trunk LDT1 that accommodates the leased line L3, and the outside line accommodation terminals O1 to O3 are connected to the incoming call connection terminal IC1 of the leased line trunk LDT1 that accommodates the leased line L3.
The central office line trunk COT1 accommodating the local office trunk IOT1, and the outgoing connection terminal OG1 of the dedicated line trunk LDT1 are connected. Also exchange machine
EX2 call path switch SW2 extension receiving terminal E
4 and E5 are the incoming connection terminal LC2 of the leased line trunk LDT2 that accommodates the leased line L3, and the extension C.
An internal line trunk COT2 accommodating the central office line L2 is connected to the external line accommodating O4 to O6, and an internal trunk trunk IOT2 accommodating the central office line L2.
It is connected to the outgoing connection terminal OG2 of the leased line trunk LDT2. Central control unit CC in exchange EX1
1' and the central control unit CC2' in the exchange EX2 are also provided with switching control functions XT1 and XT2, respectively (switching control functions XT1 and XT
The switching control function of No. 2 is the same as in FIGS. 4 and 5). Assuming that extension A and office line L1 are currently talking,
The communication path switch SW1 closes the cross point X1 and connects the extension line accommodation terminal E1 and the outside line accommodation terminal O.
Connect with 1. In this state, extension A becomes central line L1.
When a predetermined hold operation is performed to transfer the call to extension B, the central controller CC1' switches the call path switch.
SW1 is made to open cross point X1, and a hold tone is sent from office line trunk COT1 to office line L1. Then, when extension A selects the telephone number of extension B, the central controller CC1 calls extension B,
When extension B responds, the communication path switch SW1 closes cross points X2 and X3 to connect extensions A and B. When extension A requests extension B to make a call to central office line L1, the central controller CC
1 is the cross point X2 to the communication path switch SW1
And open X3 and cross point
4 to connect the extension line accommodation terminal E2 and the outside line accommodation terminal O1. As a result of the above, extension A and office line L
Calls with 1 are transferred to extension B. Next, extension A is transferred to extension C, which is housed in exchange EX2, to central office line L1.
If you wish to transfer a call to someone else, put the call on hold in the same way as above, and then dial the calling number and extension C to dedicated line L3.
When a telephone number is selected, the central control unit CC1' of the exchange EX1 switches the call path switch SW
1 opens crosspoint
5 to connect the extension line accommodation terminal E1 and the outside line accommodation terminal O3, and also connect the dedicated line trunk LDT1.
Set to outgoing connected state. On the other hand, in the exchange EX2, the leased line trunk LDT2 is activated via the leased line L3 and becomes connected to an incoming call. Next, when extension A selects the telephone number of extension C, the telephone number information is transferred to leased line trunk LDT1 and leased line L3.
and is transmitted to the central controller CC2' via the leased line trunk LDT2. The central control unit CC2', which received the telephone number of extension C, calls extension C.
When a response from extension C is detected, the central controller CC
2' causes the leased line trunk LDT2 to send a response signal to the leased line trunk LDT1 via the leased line L3, and activates the switching control mechanism XT2.
The switching control mechanism XT2 switches the leased line trunk LDT2 from the incoming connection state to the outgoing connection state, and also causes the communication path switch SW2 to switch the cross point
10 to connect the extension line accommodation terminal E5 and the outside line accommodation terminal O6. On the other hand, dedicated line trunk
When LDT1 receives the response signal, the central controller
CC1' activates the switching control mechanism XT1. The switching control mechanism XT1 switches the leased line trunk LDT1 from the outgoing connection state to the incoming connection state, and
The communication path switch SW1 opens the cross point X5 and closes the cross points X8 and X9, thereby connecting the extension receiving terminals E1 and E3 via the trunk IOT1 within the local office. As described above, extension A includes the extension circuit LC1, the extension accommodation terminal E1 of the call path switch SW1, the cross points X8 and X9, the extension accommodation terminal E3, the internal trunk IOT1,
Incoming connection terminal IC1 of leased line trunk LDT1, leased line trunk LDT1 in incoming connection state, leased line L3, leased line trunk in outgoing connection state
LDT2, leased line trunk LDT2 outgoing connection terminal
It is connected to extension C via OG2, cross point X10 of call path switch SW2, and extension circuit LC3. When extension A requests extension C to resume a call with central office line L1, central controller CC1' causes call path switch SW1 to open crosspoints X8 and X9, close crosspoint X11, and close the extension receiving terminal. E3 and outside line accommodation terminal O1
connect with. As a result, extension C is the extension circuit
LC3, communication path switch SW2 cross point X
10. Leased line trunk LDT2 outgoing connection terminal OG
2. Leased line trunk LDT2 in outgoing connection state;
Leased line L3, leased line trunk in incoming connection state
LDT1, leased line trunk LDT1 incoming call connection terminal
IC1, extension receiving terminal E of communication path switch SW1
3. Cross point X11 and outside line accommodation terminal O
1 and the office line L1 via the office line trunk COT1, and calls to the office line L1 are transferred from extension A to extension C.

As is clear from the above description, according to this embodiment, extension A, which is currently talking to central office line L1, calls extension C via dedicated line L3 after putting central office line L1 on hold, and when extension C answers, the central The switching control mechanism XT1 of the control device CC1' is the dedicated line trunk in the outgoing connection state.
The LDT1 is switched to the incoming connection state, and the switching control mechanism XT2 of the central controller CC2' switches the leased line trunk LDT2, which is in the incoming connection state, to the outgoing connection state. As a result, the central controller CC1' is connected to extension A.
When the call is restored, the call route switch
By opening cross points X8 and X9 of SW1 and closing cross point X11,
A call to the central office line L1 can be transferred to extension C.

It should be noted that Figures 2 to 6 are only one embodiment of the present invention, and for example, transfer of a central office line call is performed by an exchange.
It is not limited to calls made from extension A accommodated in EX1 to extension C accommodated in exchange EX2, and it is also possible for extension C to transfer a call with central office line L2 to extension A. Central controllers CC1' and CC2' both have switching control functions XT1 and XT
2, the effects of the present invention remain unchanged in either case. In addition, external lines are central lines L1 and L.
2, and many other modifications such as extension lines or dedicated lines connected to other private branch exchanges may be considered, but the effects of the present invention will not change in any case. Furthermore, the configurations of the exchanges EX1 and EX2 are not limited to those shown in the drawings, and many other modifications may be considered, but the effects of the present invention will not change in any case.

(g) Effects of the Invention As described above, according to the present invention, in the private branch exchange, calls with outside lines can be transferred to extensions accommodated in other exchanges connected by dedicated lines, thereby improving the convenience of the private branch exchange. will improve.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a conventional transfer control system, FIGS. 2 and 3 are diagrams explaining an inter-exchange connection system according to an embodiment of the present invention, and FIGS. 4A and B are diagrams at the originating exchange. FIGS. 5A and 5B are diagrams illustrating the switching control function in the destination exchange, and FIG. 6 is a diagram illustrating the detailed configuration of the exchange according to an embodiment of the present invention. In the figure, A, B and C are extensions, CC1,
CC1', CC2 and CC2' are central control units;
COT1 and COT2 are office line trunks, E1 to E5 are extension line accommodation terminals, EX1 and EX2 are exchanges, IC1 and IC2 are incoming call connection terminals, IOT1 and IOT2 are trunks within the own office, L1 and L2 are office lines, L3 is a dedicated line, LC1 to LC3 are extension circuits, LDT1 and LDT2 are leased line trunks,
MEM1 and MEM2 are storage devices, O1 to O
6 is an outside line receiving terminal, OG1 and OG2 are outgoing connection terminals, r1 and r2 are changeover switches, SW1
and SW2 are communication path switches, X1 to X11
indicates a cross point, and XT1 and XT2 indicate a switching control function.

Claims (1)

[Claims] 1. Incoming connection terminals for extension lines and lines from other exchanges are accommodated in extension line accommodation terminals, and outgoing connection terminals for lines from said other exchanges are accommodated in external line accommodation terminals, and connections from multiple exchanges mutually connected by said lines are accommodated. In the private branch exchange configured, a first extension housed in the first exchange calls a second extension housed in the second exchange via the line, and the second extension responds. The second exchange that has detected the response signal returns a response signal to the first exchange via the line, connects the second extension to the originating connection terminal of the line, and connects the second exchange that has received the response signal. An inter-exchange connection system characterized in that a first exchange switches the connection of the first extension from an outgoing connection terminal to an incoming connection terminal of the line.