JPH02128560A - Private branch exchange capable of responding to did dil incoming - Google Patents

Abstract

PURPOSE:To respond to a call regardless of the busy state of an extension telephone set of the call destination by controlling a switch means to temporarily connect a signal tone sending means by a connection control means at the time when a DID(direct in dial) DIL(direct in line) call comes to one extension terminal and the extension terminal is busy. CONSTITUTION:When a DID DIL call comes to one of extensions (extension telephone sets) 1 and 2 from a trunk line 10, a connection control means (B board controller) 6 controls a switch means 9 and temporarily connects a signal tone sending means 4 to this extension terminal 1 or 2 to send a DID DIL incoming indicating signal tone if this extension terminal 1 or 2 is busy. When the extension terminal 1 or 2 to which the DID DIL call comes responds to the call by hooking or dialing operation, the switch means 9 is controlled to connect the trunk line 10 to the extension terminal 1 or 2. Thus, one of extension terminals 1 and 2 receives the call from the trunk line 10 while being busy and alternately speaks with the other of terminals 1 and 2 and the trunk line 10 or these three parties speak with one another.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to telephone exchanges, and more specifically to DIDs.

This relates to a private branch exchange capable of responding to DTL incoming calls.

(Prior Art) There are two types of response methods for incoming calls on a central office line in a private branch exchange: a relay response method and a distributed response method. In this case, an incoming call display device such as a station line display board or a tone ringer is provided as a common answering device, and these devices are used to respond to incoming calls.

For example, in private electronic branch exchanges, incoming calls from central office lines are automatically connected to extension subscribers without the intervention of attendants at relay stations, using direct in-air (DID) and tie-left in-line (DIL) call response methods. There is.

This call response method has the advantage that calls can be received directly from outside lines to extension users without the intervention of an attendant. If the desired extension is free, the caller calls that extension, and when the extension user goes off-hook, the incoming call can be answered on the central office line. However, if the extension is busy, the incoming call from the central office line is answered at the relay stand, and the operator interrupts the extension call to notify the extension of the incoming call from the central office. Alternatively, if a distributed response system is used, incoming calls from the central office line can be visually and audibly displayed on the common response equipment, and responses can be made using other extension telephones.

(Problems to be Solved by the Invention) In conventional private branch exchanges capable of responding to incoming calls using DID and DIL, common response equipment is required in the case of the distributed response method as a countermeasure for answering busy extensions; In this case, the disadvantage was that it was not possible to answer incoming calls on the central office line while the attendant was busy talking.

The present invention eliminates the drawbacks of the prior art, and allows DID and DID to be used even when the extension is busy, without the need for common answering equipment.
The purpose of the present invention is to provide a private branch exchange capable of responding to incoming DIL calls.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a DID and DIL incoming call response system that connects incoming calls from a central office line directly to an extension terminal by selecting an extension of the caller. The private branch exchange is
DID from the central office line, DID that displays incoming DIL calls,
A signal tone transmitting means for generating a DIL incoming call indicating signal tone, a plurality of extension terminals, a central office line, and a signal tone transmitting means are accommodated,
switch means for setting a selective connection between them; and connection control means for controlling the switch means to set the selective connection; When a DID or DIL call arrives, if this extension terminal is free, the switching means is controlled to connect the central office line to this extension terminal, and if this extension terminal is busy, the switching means is controlled. and then temporarily connects a signal tone sending means to that extension terminal and sends a DID to that extension terminal.
A DIL incoming call indicating signal tone is transmitted, and when this extension terminal responds, the switch means is controlled to connect the central office line to the extension terminal.

(Function) According to the present invention, when there is a DID or DIL call from the central office line to one extension terminal, and if this extension terminal is busy, the connection control means controls the switch means to switch the connection control unit to the other extension terminal. A signal tone sending means is temporarily connected to the extension terminal, and llID and DIL incoming call indicating signal tones are sent to the extension terminal. In that case, if this extension terminal is already connected to another extension terminal, the switch means is controlled to connect the signal tone sending means to this other extension terminal, and a hold signal tone indicating that the connection is on hold is sent out. You may let them. When the extension terminal receiving the DID or DIL call responds, for example, by hooking or dialing, the switch means is controlled to connect the central office line to the extension terminal. According to this DID/DIL incoming call response system, an extension terminal can receive an incoming call from a central office line while it is busy and can communicate with other extension terminals and the central office line alternately, or between these three parties. .

(Example) Next, DID and DIL according to the present invention will be described with reference to the attached drawings.
An embodiment of a private branch exchange capable of responding to incoming calls will be described in detail.

FIG. 1 shows a relay system of an embodiment of a private branch exchange capable of responding to DID and DIL incoming calls. This private branch exchange connects incoming calls via the normal relay stand 5 for incoming calls from the central office line by selecting a representative number, and then connects the incoming calls using the DID.

DID for incoming calls from DIL central office line trunk 3.

This is an electronic exchange that receives a DIL subscriber number and connects an extension telephone 1 or 2 to a central office trunk 3. When connecting an incoming DID or DIL call from the central office line 10, if the target extension, for example, extension telephone 1, is busy with another extension or central office line, the exchange will connect the extension telephone 1 to that extension telephone 1. DID, DID indicating incoming DIL call,
A DIL incoming call indicating signal tone is sent out, and when the telephone 1 responds, the connection of the other party's device, for example, the extension telephone 2, which is currently being called is suspended, and the target telephone 1 is connected to the central office line.

In the figure, the private branch exchange has a call path switch 9,
This accommodates extension terminals such as extension telephones 1 and 2, a relay stand 5, office line trunks 3 such as DID and DIL office line trunks, and a tone trunk 4 for transmitting signal tones, and a central control unit (CPU). This is a switch circuit network that selectively establishes a communication path between them under the control of the network. The tone trunk 4 includes a signal tone sending circuit that sends out not only normal signal currents and signal tones such as a ringing signal and a hold tone, but also DID and DIL incoming call indicating signal tones in this embodiment. D.I.D.
, For example, as shown in FIG. 2, the DIL incoming call indicating signal tone uses a signal tone of 400 Hz to 800 Hz. Note that these devices accommodated in the switch 9 are usually
Although there are a plurality of devices not limited to the number shown in the figure, only the number necessary for understanding the present invention is shown in the figure.

Connection control of the exchange is performed by a storage program type connection control means comprising a central control unit 7 and a memory device 8 connected thereto. The central control device 7 performs connection control such as call processing according to a program stored in the memory device 8. For example, when an incoming call based on representative number selection arrives from the central office line IO, the incoming call information is sent to the relay console 5 via the relay console control device 6, and an incoming call is displayed on the relay console 5. As a result, connection to the relay board is performed through the intervention of the operator.

Regarding incoming calls to DID and DIL central office line trunk 3,
Incoming connections are made according to the DID and DIL response methods. For example, when extension telephones 1 and 2 are connected to each other and are in the middle of a call, DID,
When a DIL call is received, the central control device 7 issues a DID call.
, An example of the processing operation for incoming DIL calls will be explained with reference to the flowchart of FIG.

First, in step 100, the DID, DIL incoming call is
ID.

111L, the central controller 7 causes a response signal to be sent from the office line trunk 3 to the office line IO under program control in step 101. In response, the calling party sends a selection signal based on the DID or DIL number, which is received by the central office line trunk 3. The central control unit 7 decodes this and identifies that this call is to ring an extension telephone, for example l. Therefore, in step 102, the central control unit 7 checks whether the extension telephone 1 on the called side is idle. If it is vacant, the switch 9 is controlled in step 103 to send a calling signal to the extension telephone 1 in the normal procedure. In the next step 104, when the extension telephone 1 goes off-hook and responds, this is detected and a ring trip is performed, and in step 105, the switch 9 is controlled to connect the telephone 1 to the central office trunk 3 and make a call.

Monitoring of the end of the call is carried out on the central office line trunk 3. Step 1
At 0B, the central control unit 7 controls the switch 9 in response to the termination of the call, and releases the connection path between the telephone 1 and the office line trunk 3.

By the way, in step 102, if the extension telephone 1 is connected to the extension telephone 2 via the switch 9 and a call is in progress, the central control unit 7 identifies this and proceeds to step 107. In step 107, the central controller 7 controls the switch 9 to temporarily disconnect the telephones 1 and 2. At this time, the switch 9 is controlled to send a holding tone indicating that the connection is on hold to a telephone other than the destination of the DID or DIL incoming call, in this example telephone 2, using the normal procedure. At the same time, the extension telephone 1 is connected to the tone trunk 4 via the switch 9, and the tone trunk 4 is caused to send out DID and DIL incoming call indicating signal tones.

This signal tone has a frequency of 400Hz as illustrated in Figure 2.
A signal tone of 800Hz to 800Hz is emitted for a predetermined period, for example 0.
It is sent continuously for about 2 seconds. This is sent to telephone 1 and listened to by that extension. After the central control device 7 causes the tone trunk 4 to send out the DID and DIL incoming call display signals for a predetermined period of time, the central control device 7 controls the switch 9 again to restore the extension connection between the telephones 1 and 2, and the extension calls between the two are terminated for a predetermined period. A period of time, for example about 10 seconds to 60 seconds, is allowed. D
This process is repeated until extension l responds to the incoming ID and DIL calls.

When the extension telephone 1 responds to the incoming DID or DIL call by hooking or dialing a special number in step 108, the central controller 7 detects this and controls the switch 9, as shown in step 108. , connects the office line lO to the extension telephone l. Thus, D.D.
A conversation with the IL call receiving telephone 1 is started. During this time, the hold tone is sent to the other telephone 2 in the same manner as described above (step 110). The extension person 2 may listen to the hold tone and wait, or may go on-hook to restore the extension connection. In the latter case, the central controller 7 controls the switch 9 to restore the communication path for the telephone 2.

When the other extension telephone 2 is on hold, in this embodiment, one extension telephone 1 is operated to send the DID.

It is possible to make alternate calls or champion calls for DIL connections. In step 111, e.g.
When a short hook is performed at Change the connection such as connecting to 10. or
In response to the hooking, the central control device 7 connects the telephone 1 and the central office line 10 and also connects the extension telephone 2 to make a champion call, or excludes the telephone 2 from the three-way call. Good too.

The condition for terminating a call with the central office line 10 is based on recovery on the central office line side or an on-footer on the extension telephone 1 or 2 that is currently communicating with the central office line 10. In step 112 the central controller 7
controls the switch 9 in response to the detection of the end of the call, and restores the connection between the office line trunk 3 and the telephone set 1 or 2.

In this explanation, an example was shown in which extension telephone 1 is busy with another extension telephone 2, but extension telephone 1 may be busy simply due to an off-footer, or other telephones may be connected to it first, or telephone 1 may be busy with other extension telephone 2. Similar DID and DIL incoming call response control is performed even when connected to the central office line IO and busy.

(Effects of the Invention) According to the present invention, when a DID or DIL call is received, even if the extension telephone of the destination is busy, the connection to other telephones is suspended and the telephone responds to the received DID or DIL call. Can be done. Therefore, the original advantages of the DID and DIL termination systems are not lost, and the common response equipment required in the conventional distributed response system is not required.

[Brief explanation of the drawing]

FIG. 1 shows [110. FIG. 2 is a relay system diagram showing an example of a private branch exchange capable of responding to DIL incoming calls; FIG. 2 is a waveform diagram showing an example of the DID and DIL incoming signal tone applied to the embodiment shown in FIG. 2 is a flowchart illustrating an example of the operational flow of DID and DIL incoming call response control in the same embodiment. Explanation of symbols of main parts 1.2. . 3. 4. 7. 8. 9. Extension telephone DID, DIL Office line trunk tone trunk central controller memory device switch

Claims (1)

[Scope of Claims] 1. A private branch exchange capable of responding to incoming DID and DIL calls that connects incoming calls from a central office line directly to an extension terminal according to the caller's extension selection, which exchange receives incoming DID and DIL calls from a central office line. Display DID, DI
a signal tone transmitting means for generating an incoming call indicating signal; a switch means for accommodating a plurality of extension terminals, the central office line and the signal tone transmitting means and establishing a selective connection therebetween; connection control means for controlling and setting the selective connection, the connection control means comprising:
When an ID or DIL call is received, if the one extension terminal is free, the switching means is controlled to connect the central office line to the one extension terminal, and if the one extension terminal is busy, the switch means is connected to the central office line. , controlling the switch means to temporarily connect the signal tone sending means to the one extension terminal to send the DID and DIL incoming call display signal tones to the one extension terminal; A private branch exchange capable of responding to incoming DID and DIL calls, characterized in that when a response is received, the switch means is controlled to connect the office line to the one extension terminal. 2. The exchange according to claim 1, wherein the signal tone sending means generates a hold signal tone to indicate to the extension terminal that the connection is on hold, and the connection control means receives a DID or DIL call from the central office line. If the one extension terminal to be called is already connected to another extension terminal, the switch means is controlled to connect the signal tone sending means to the other extension terminal, and the hold signal is transmitted to the other extension terminal. A private branch exchange characterized by transmitting sound.