JPH06334744A - Call back method in private branch exchange and private branch exchange - Google Patents

Abstract

PURPOSE:To call back a user of an extension terminal equipment without encountering a busy extension by a call back from a connection destination of an emergency call when said extension terminal equipment is interrupted after the connection of the emergency call to a police station or a fire station from the extension terminal equipment accommodated in a private branch exchange. CONSTITUTION:Upon the receipt of an interrupt signal from an extension terminal equipment 6 by a call processing unit 7, a line management section 11 and a line management memory 15 set an extension having been up to now to be a reserved state till a line state discrimination section 10 discriminates an external line to which an emergency call is connected to be an idle state and when a callback signal reception section 14 receives a callback signal, a call processing section 12 uses the reserved extension to receive the call to the extension terminal equipment 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a private branch exchange (PBX).
For more details on the call back method and private branch exchange in the above, when the extension terminal is disconnected after the emergency call from the extension terminal accommodated in the PBX to the police, fire department, etc., the call back from the emergency call destination is made again. The present invention relates to a call back method and a private branch exchange in a PBX that can be received when a signal is received.

[0002]

2. Description of the Related Art Generally, it is common to make an emergency call from a general subscriber to a police or fire department by using a telephone line. In this case, after the general subscriber disconnects the call, the police
The called party (generally an operator) such as a fire department may call the calling subscriber again for confirmation. In addition, although PBXs are installed in many buildings and offices, an extension terminal accommodated in the PBX connects an emergency call to the police, fire department, etc. via the PBX, and the extension terminal is disconnected after use. later,
It is naturally conceivable that the called party (generally an operator) of the police, fire department or the like may call back the calling subscriber for confirmation.

FIG. 4 is a block diagram of a conventional private branch exchange. In the figure, 21 is a private branch exchange (PBX).
nge), 22 is a net, 23 is an outside line circuit, 24 is a switching circuit,
25 is an extension circuit, 26 is an extension terminal, 27 is a call processing device,
Reference numeral 28 is a storage device, 29 is an extension circuit control unit, 30 is a line management memory, 31 is a line management unit, 32 is a call processing unit, 33 is an outside line circuit control unit, and 34 is a call back signal receiving unit. The exchange circuit 24 forms a communication path between the extension circuit 25 and the outside circuit 23.

The extension circuit 25 controls an interface with the extension terminal 26. The outside line circuit 23 is connected to the network 2.
It controls the interface with 2. The call processing device 27 and the storage device 28 both control the switching circuit 24, but the call processing device 27 includes a call processing unit 32.
The internal line circuit control unit 29, the external line circuit control unit 33, the line management unit 31, and the call back signal receiving unit 34. The storage device 28 further includes a line management memory 30.
It is configured with. The extension circuit control unit 29 is for controlling the extension circuit 25, and the line management unit 31 is for making the management state of the line empty or blocked.
The call processing unit 32 controls the call state, the outside line circuit control unit 33 controls the outside line circuit 23, and the call back signal receiving unit 34 receives the call back signal from the connection destination of the emergency call. It is a thing. The line management memory 30 is a table for managing the status of the line being idle / closed.

FIG. 5 is a flow chart for explaining the control state in the call processing section. Hereinafter, each step (S) will be described in order. Initially, it is assumed that communication is in progress (S1), and thereafter, in S2, the call processing unit 32 causes the extension terminal 2 to
When the disconnection signal from 6 is received, the line between the switching circuit 24 and the extension terminal 26 (hereinafter, the line between the switching circuit 24 and any extension terminal accommodated in the PBX is called an extension) is disconnected and released. (S3), it becomes empty (S4). On the other hand, when the call back signal receiving unit 34 receives the call back signal from the police / fire department after disconnecting the call from the extension terminal 26 side, it notifies the call processing unit 32 that the call back signal has been received. The call processing unit 32 that has received the receipt notification of the call back signal
Acquires an extension (S6). If the extension can be acquired, the YES route of S7 is taken, the call setting signal is transmitted to the extension terminal 26 (S8), and the response signal from the extension terminal 26 is received (S9), the call is returned to the network 22. A response signal to the signal is transmitted (S10) and communication is in progress (S11).

If the extension cannot be acquired in S7, a signal for rejecting the call setup is transmitted to the network 22 in S13 (S13), and the system becomes idle (S14). In this way, when the extension terminal user disconnects, the line connection between the switching circuit 24 and the extension terminal 26 is disconnected according to the communication protocol so that the extension can be used for another call. When the call is released, that is, the extension management state is empty, and when a call back signal is received from an operator such as police or fire department, it is regarded as a new incoming call, that is, a new extension is acquired and the extension terminal user is notified. You have an incoming call.

[0007]

However, in such a conventional call back method, since the extension has already been released, the extension is used for another call, so that the operator such as police or fire department can use it. When the call is returned, there is a possibility that the extension is busy and a new extension cannot be acquired and the call cannot be received.

The present invention has been made in view of the above circumstances, and can respond to a call back from an operator such as a police or fire department without calling the extension terminal busy and call back the extension terminal user. An object of the present invention is to provide a call back method and a private branch exchange that can be used in the private exchange.

[0009]

In order to achieve the above-mentioned object, the present invention provides (1) one or more outside wires, and
Private branch exchange (PB) accommodating one or more extension terminals
In X), when the call processing unit receives a disconnect signal from the extension terminal after connecting the emergency call from the extension terminal through the extension circuit, the switching circuit, and the outside circuit, the connection destination of the emergency call is the outside line. Until the communication line on the side is released, keep the communication line on the extension side that was being used until then,
When a call back signal from the connection destination of the emergency call is received, the extension side communication line is used to receive the call to the extension terminal, or (2) from the extension terminal or the network. Call processing section for receiving and transmitting signals relating to call control, a line management section for setting the line management state to empty, blocked, or reserved, and a call setting signal from the network side or extension terminal side If the processing unit does not have an empty extension at the time of reception, it judges whether the external line used when connecting the emergency call is in an empty state or in a blocked state. Section to instruct the section to change the management state of the extension from the reserved state to the idle state, and to receive the call back signal from the emergency call destination With a call back signal receiving unit that notifies the department It is obtained by further comprising a et consisting call processor.

[0010]

[Function] When an extension terminal disconnects a call after connecting an emergency call from the extension terminal, the extension used until that time is
Until the line status determination means determines that the external line used up to that time is available for another call,
If you make a reservation for a call back from the emergency call destination and receive a call back from the emergency call destination, use the extension that is in the reserved state to receive the call at the extension terminal. Is done.

[0011]

Embodiments will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining an embodiment of a call back method and a private branch exchange in a private branch exchange according to the present invention. In the drawing, 1 is a private branch exchange (PBX: Private Branch).
Exchange), 2 is a network, 3 is an outside line circuit, 4 is a switching circuit,
5 is an extension circuit, 6 is an extension terminal, 7 is a call processing device, 8 is a storage device, 9 is an extension circuit control unit, 10 is a line state determination unit,
Reference numeral 11 is a line management unit, 12 is a call processing unit, 13 is an outside line circuit control unit, 14 is a call back signal receiving unit, and 15 is a line management memory.

The exchange circuit 4 forms a communication path between the outside line circuit 3 and the extension line circuit 5, the outside line circuit 3 controls an interface with the network 2, and the extension line circuit 5 is an extension terminal 6 Control the interface with. Also,
The call processing device 7 and the storage device 8 are both the switching circuit 4
The call processing device 7 controls the call processing unit 1
2, an extension circuit control unit 9, a line state determination unit 10, a line management unit 11, an outside line circuit control unit 13, and a call back signal reception unit 14.
And the storage device 8 further includes a line management memory 15. The call processing unit 12 controls the call state, and more specifically, the extension terminal 6
Alternatively, it receives signals related to call control from the network 2, analyzes signals related to call control received from the extension terminal 6 or the network 2, manages protocol state, and sends signals related to call control to the extension terminal 6 or the network 2. Is to do.

The line management unit 11 sets the line management state to an empty state, a closed state, or a reserved state (reservation is performed for an extension used when an emergency call is connected). When the call processing unit 12 receives a call setting signal from the network side or the extension terminal side, the line state determination unit 10 determines that the external line used at the time of connecting an emergency call is free if there is no extension in a free state. It is determined whether the state is a closed state or a closed state, and if it is a free state, the call processing unit 12 is instructed to change the extension management state from a reserved state to a free state. The extension circuit control unit 9 is for controlling the extension circuit 5, and the extension circuit control unit 13 is for controlling the extension circuit 3. Recall signal receiver 14
Receives a call back signal from an operator such as police or fire department, that is, a call back signal from a connection destination of an emergency call, and when received, notifies the call processing unit 12 that the call back signal from the operator has been received. It is a thing. The line management memory 15 is a table for managing the state of free / closed / reserved lines.

2 and 3 are flow charts for explaining the control state in the call processing unit. Hereinafter, each step (S) will be described in order. First, during communication (S
1), then the call processing unit 12 at S2,
When the disconnection signal is received from the extension terminal 6, the extension is disconnected / released (S3), it is determined in S4 whether the connected call is a police / fire service call, and if so, in S5, until now. The extension that has been used is reserved and becomes empty (S6). After the call is disconnected from the extension terminal 6 side, when the call processing unit 12 receives the call back signal from the call back signal receiving unit 14 from the police / fire department (S7), the reserved extension is acquired in S8, and the extension is reserved. A call setup signal is transmitted to the terminal 6 (S
9) After receiving the response signal from the extension terminal 6 (S10), the acquired extension is connected (S11) and the response signal to the call back signal is transmitted to the police / fire department (S1).
2), communication is in progress (S13).

After disconnecting the call from the extension terminal 6 side,
When the call processing unit 12 receives the call setting signal (S15), S
At 16, it is determined whether or not there is an empty extension. If there is no free extension, the NO route of S16 is taken and the line state determination unit 10 determines the police /
Determine whether the outside line used when the fire call was connected was open or closed.

If the outside line is in an empty state, that is, if no call back from the police / fire department occurs, the YES route of S23 is taken and the line state determination unit 1
0 instructs the call processing unit 12 to change the state of the extension, which has been reserved for the return call from the police / fire department in S5, to the empty state, and the call processing unit 12 The state of the extension is changed to an empty state (S24). After that,
The call processing unit 12 acquires the extension changed to the idle state (S25) and transmits a call setting signal to the called side (S2).
6). The call processing unit 12 that has received the response signal from the receiving side (S27) connects the acquired extension (S28), transmits a response signal to the calling side (S29), and is in communication (S30). .

Further, in S23, the line state judging section 10
As a result of determining whether the state of the outside line used when the police / firefighting call was connected was an empty state or a closed state,
If the outside line is blocked, the NO route of S23 is taken, and the call processing unit 12 transmits a signal rejecting the call setting to the calling side (S31) and becomes idle (S31).
6). In S16, if there is an empty extension, the YES route of S16 is taken and the call processing unit 12 acquires an empty extension (S17), and a call setting signal is sent to the called side. It is transmitted (S18). Upon receiving the response signal from the destination side (S19), the call processing unit 12 connects the acquired extension (S20) and transmits the response signal to the originating side (S19).
21), communication is in progress (S22). In addition, in S4, as a result of determining whether the connected call is a police / fire service call,
If not, it becomes empty (S14).

In this way, when the call processing unit 12 receives the disconnection signal, it determines whether it is a police / fire service call. If it is a police / fire service call, the extension is reserved and then the call back signal is received. Then, the call processing unit 12 connects the call using the reserved extension. Also, the cancellation of the reservation status can be done by the police
It is performed when the result of determining the state of the outside line used when the fire fighting call was connected is an empty state. That is, when the call processing unit 12 receives a disconnection signal from the extension terminal 6, it immediately disconnects the extension used at that time and changes the state of the extension in the line management memory 15, but it is not available. It does not change to state and is not used for another call. In other words, it is changed to the state of being reserved, which is neither empty nor blocked.

After that, if there is an outgoing call from the same access interface as the extension terminal 6 or if there is an incoming call to the same access interface as the extension terminal 6, if there is an available extension, The call is connected using the extension, but if there is only the extension in the reserved state or the extension in the blocked state and there is no extension in the empty state, when the police / fire service call is connected Determine the status of the external line you were using, and if the result of the determination is that the extension is in the reserved state, change the extension to the idle state and use this extension to connect the call. If the result of the determination is that the call is blocked, the call is not connected. When a call back signal from an operator such as police or fire department is received, a reserved extension is assigned and a call setting signal is transmitted to the extension terminal 6 as a new call using the extension. By that, it makes an incoming call. As a result, the operator, such as police or fire department, can always call back to the extension terminal of the PBX, and as a result, it greatly contributes to the improvement of police and fire department calls. .

[0020]

As is apparent from the above description, the present invention has the following effects. That is, PBX
When the call processor receives a disconnection signal from the extension terminal of the PBX after connecting the emergency call from the extension terminal of No. 1 through the extension circuit, the switching circuit, and the outside line circuit, the extension used until that time Until the connection destination of the emergency call disconnects / releases the external line that has been used up to that time, and is reserved for returning from the connection destination of the emergency call. If you receive a call back signal from the front,
Since an extension terminal in the reserved state is used to receive an incoming call at the extension terminal of the PBX, when the operator such as police or fire department calls back to the extension terminal of the PBX,
There is an advantage that it will be possible to call back at any time, and it will greatly contribute to the improvement of police and fire fighting calls.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining an embodiment of a call back method and a private branch exchange in a private branch exchange according to the present invention.

FIG. 2 is a flowchart (No. 1) of processing for explaining an embodiment of a call back method in a private branch exchange according to the present invention.
Is.

FIG. 3 is a flowchart (No. 2) of processing for explaining an embodiment of a call back method in the private branch exchange according to the present invention.
Is.

FIG. 4 is a block diagram showing a conventional private branch exchange.

FIG. 5 is a flowchart of a process for explaining the operation of a conventional private branch exchange.

[Explanation of Codes] 1 ... Private branch exchange (PBX)
e) 2 ... network, 3 ... external circuit, 4 ... switching circuit, 5 ... extension circuit, 6 ... extension terminal, 7 ... call processing device, 8 ... storage device,
9 ... Extension circuit control unit, 10 ... Line state determination unit, 11 ... Line management unit, 12 ... Call processing unit, 13 ... External line circuit control unit, 1
4 ... callback signal receiving unit, 15 ... line management memory.

Claims (2)

[Claims] 1. A private branch exchange accommodating one or a plurality of outside lines and one or a plurality of extension terminals, after connecting an emergency call from the extension terminal through an extension circuit, a switching circuit, and an outside line circuit, When the call processing unit receives the disconnection signal from the extension terminal, the extension side communication line that has been used until that time is reserved until the emergency call connection destination releases the outside line communication line. When a call back signal from the connection destination of the emergency call is received, the call back in the private branch exchange is characterized in that the extension side communication line is used to receive the call. Method. 2. A call processing unit for receiving and transmitting a signal related to call control from an extension terminal or a network, a line management unit for making a line management state empty, blocked, or reserved, and a network side or an extension line. If the call processing unit receives a call setting signal from the terminal side, and if there is no extension in the idle state, it is determined whether the external line used for connecting the emergency call is in the idle state or the blocked state, and the idle state is set. In the case of the state, the line state determination unit for instructing the call processing unit to change the management state of the extension from the reserved state to the idle state, and the call back signal from the destination of the emergency call are sent. A private branch exchange having a call processing device comprising a call back signal receiving unit for receiving and notifying the call processing unit of reception.