JP2001008248A - Key telephone system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key telephone system that can monitor emergency notice information. SOLUTION: In the case that an optional extension telephone set makes an emergency call to a prescribed emergency called destination, a telephone set control section retrieves emergency destination number storage section, detects the presence of registration of the telephone number of the emergency called destination, discriminates the occurrence of an emergency call when the telephone number is registered (S104), and informs a prescribed key telephone system about the telephone number of the emergency caller and the telephone number of the emergence called party (S114). When the prescribed key telephone system is busy, this busy call is forcibly interrupted or held temporarily (S116), a voice path between the emergency caller and the prescribed key telephone system is connected (S117), and when the prescribed telephone set replies the call (S118), emergency notice information exchanged between the emergency caller and the emergency called party can be monitored (S119).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key telephone apparatus, and more particularly, to a key telephone apparatus having a function of transferring emergency notification information in an emergency call from a single telephone or a key telephone to an office line, and emergency notification information for notifying other key telephones. About.

[0002]

2. Description of the Related Art In a factory or a building, a key telephone apparatus containing a plurality of single telephones and a plurality of key telephones as a plurality of central office lines and extension telephones has become widespread. In the event of an accident or fire in a factory or building, the emergency call from the nearest extension telephone to the person in charge or the security office, or an emergency call from the nearest extension telephone, or the in-house notification system, besides the 119 and 110 calls via the local line Is performed.

Conventionally, the following several methods have been proposed as emergency call methods in a button telephone apparatus that accommodates an extension telephone including a plurality of office lines, a plurality of single telephones, and a plurality of key telephones. .

In the first method, a person who has found an accident or fire performs an office line transmission operation from the nearest extension telephone to capture the office line and
A 19th and 110th call is made, and then an extension call operation is performed and an emergency call is made again to the responsible person, the security room or the in-house report system.

A second method is an emergency telephone number (110, 119) dialed from a key telephone, which is an extension telephone set with outside line capture restriction, following a call key operation.
No.) is compared with an emergency telephone number registered in the memory in advance, and when they match, the outside line capturing restriction is released to capture the corresponding outside line, and the emergency telephone number is automatically dialed. 248191.

A third technique is to form a communication path between the key telephone and the central office when an abnormal signal is received from a gas abnormality detecting circuit or a gas abnormality detecting circuit accommodated in the key telephone. Automatically sends a call to the destination exchange, connects to the destination, and transmits emergency notification information such as the subscriber number and address of the key telephone by voice signal, so that the telephone number and address of the caller can be determined in an emergency. A method for providing an accurate notification has been proposed in, for example, Japanese Patent Application Laid-Open No. 01-296791.

A fourth technique is to display the telephone number of a caller on an extension telephone during a call when an extension call (key telephone) during a call with an office line is received individually, and a response is received within a predetermined time. When there is a call, the incoming line is held and an individual incoming call is received. When there is no answer, the individual incoming call is forwarded to another extension telephone set at the time of emergency, so that emergency A method for directly listening to the business has been proposed in, for example, Japanese Patent Application Laid-Open No. 08-205214.

In a fifth method, control information (flashing of lamps, display contents, call restriction) corresponding to each urgency is registered in advance in the key telephone main unit, and the called side key telephone which has called the extension does not respond. At the time, the calling side key telephone determines the degree of urgency from the specific key information operated according to the degree of urgency, automatically sets the message weight corresponding to the pre-registered control information for each degree of urgency to the receiving side key telephone, A method of notifying the user of the called side key telephone of the urgency and restricting the outgoing call by controlling the lamp blinking control and the text display of the side key telephone is disclosed in, for example, JP-A-07-16.
No. 2918 has been proposed.

[0009]

The first method described above is based on a method in which a person who has found an accident or a fire makes an emergency call to a police station or a fire station, and a person in charge in a company, a factory, a building, a security room or a building. Since an emergency call to the system and two emergency call operations are required, there is a risk that a sufficient response at the site and a sufficient emergency situation cannot be transmitted.

[0010] The second method, Japanese Patent Application Laid-Open No. H02-24819
In the key telephone apparatus proposed in Japanese Patent Publication No. 1 (KOKAI), an emergency telephone number (110, 119, etc.) is registered in advance in a key telephone main apparatus, and a key telephone, which is an extension telephone set with outside line capture restriction, is registered. The emergency telephone number dialed after the call key operation is compared with the emergency telephone number registered in the key telephone main unit in advance, and if they match, the external line capture restriction is released and automatic dialing to the corresponding external line is performed. Therefore, in an emergency, it is possible to make an emergency call to a police station, a fire department, or the like from an extension key telephone set to be restricted from outgoing calls, but cannot make an emergency call to another extension key telephone.

Therefore, an emergency call to the responsible person in the company or factory (for example, a fire brigade) or a security room in a building must be made again separately from an emergency call to the police and the fire department. There is a danger that the emergency response and sufficient emergency situation cannot be communicated.

A third technique is that when a gas leak or a fire occurs, the key telephone apparatus sends an abnormal signal to the key telephone to notify the key telephone, and forms a communication path between the key telephone and the central office. Automatically sends a call to the destination exchange, connects to the destination, and reports emergency notification information such as the subscriber number and address of the key phone to the police station or fire department by voice signal. Can be accurately reported to police and fire departments, but emergency calls cannot be made to other extension key telephones.

Therefore, an emergency call to a responsible person in the company or factory (for example, a fire brigade) or a security room in a building must be made again separately from an emergency call to the police and fire departments. There is a danger that the emergency response and sufficient emergency situation cannot be communicated.

In a fourth method, when an individual incoming call is received by an extension key telephone that is talking to a central office line, the telephone number of the caller is displayed on the extension key telephone that is talking and a response is made within a predetermined time. When an incoming call arrives, the incoming line is held and an individual incoming call is received. When there is no answer, the individual incoming call is forwarded to another preset extension telephone. Can be heard directly, but the person who found the accident or fire must make an emergency call to the police and fire departments, an officer in the company, factory or building, a security room or an in-house notification system. Since an emergency call operation is required, there is a risk that a sufficient response at the site and a sufficient emergency situation cannot be transmitted.

[0015] The fifth method, Japanese Patent Laid-Open No. 07-16291
The key telephone apparatus proposed in Japanese Patent Application Publication No. 8-86, No. 8 discloses a method of determining the degree of urgency from specific key information operated according to the degree of urgency from an originating key telephone when an incoming call is not answered. Since the message weight corresponding to the control information according to the degree of urgency registered in advance in the main device is automatically set on the called side key telephone and the outgoing call regulation is set, and the lamp blinking control and the text display of the called side key telephone are controlled. The user of the called key telephone can be notified of the degree of urgency, but the person who discovered the accident or fire can make an emergency call to the police station or fire department, and a responsible person in the company, factory, building, security room, or in-house. Since an emergency call to the system and two emergency call operations are required, there is a risk that a sufficient response at the site and a sufficient emergency situation cannot be transmitted.

It is an object of the present invention to provide an emergency call source telephone number and an emergency call destination telephone number, and an emergency call source and an emergency call information carried out at an emergency call destination when an emergency call is made from a given extension telephone to a predetermined emergency call destination. Is to provide a key telephone device that can monitor the telephone number.

[0017]

According to the present invention, there is provided a key telephone apparatus comprising: a key telephone main apparatus for accommodating an extension telephone including a plurality of central office lines and a plurality of single telephones and a plurality of key telephones. In the key telephone device, when an emergency call is made from any of the extension telephones to a predetermined emergency destination, the telephone number of the extension telephone which is the emergency call source and the telephone number of the emergency destination are transmitted to the predetermined key telephone. It is characterized by having emergency notification means for notifying to.

Further, in a key telephone apparatus comprising a key telephone main unit accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones,
The key telephone main unit is an emergency call information branch connection for making an emergency call from any of the extension telephones to a predetermined emergency destination and branching and connecting the emergency call information performed with the emergency destination to the predetermined key telephone. It is characterized by having means.

A key telephone apparatus comprising a key telephone main unit accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones,
The key telephone main unit, when an emergency call is made from any of the extension telephones to a predetermined emergency destination, notifies the telephone number of the extension telephone that is the emergency source and the telephone number of the emergency destination to the predetermined key telephone. Emergency call information, and emergency call information branch connection means for branch connection of emergency call information between the extension telephone as the emergency call source and the emergency call destination to the predetermined key telephone. And

Further, in a key telephone apparatus comprising a key telephone main unit accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones,
The key telephone main unit includes an emergency destination number storage unit for registering a plurality of emergency destination telephone numbers corresponding to the extension telephones individually, and an emergency call from any of the extension telephones to a predetermined emergency destination. When the emergency call destination number storage unit is searched to detect the presence or absence of registration of the telephone number of the emergency call destination,
Outgoing call determining means for determining a general outgoing call when there is no registration, and for determining an emergency outgoing call when there is registration, the telephone number of the extension telephone of the emergency caller and the telephone number of the emergency call destination for the emergency outgoing call Emergency notification means for notifying the emergency call information to the predetermined key telephone, and emergency call information branching for branch connection of emergency information transmitted between the extension telephone serving as the emergency source and the emergency destination to the predetermined key telephone. Connection means.

Further, in a key telephone apparatus comprising a key telephone main unit accommodating an extension telephone including a plurality of central office lines and a plurality of single telephones and a plurality of key telephones,
The key telephone main unit includes an emergency destination number storage unit for registering a plurality of emergency destination telephone numbers corresponding to the extension telephones individually, and an emergency call from any of the extension telephones to a predetermined emergency destination. When the emergency call destination number storage unit is searched to detect the presence or absence of registration of the telephone number of the emergency call destination,
Outgoing call determining means for determining a general outgoing call when there is no registration, and for determining an emergency outgoing call when there is registration, the telephone number of the extension telephone of the emergency caller and the telephone number of the emergency call destination for the emergency outgoing call Emergency notification means for notifying to the predetermined key telephone, when the predetermined key telephone which the emergency notification means notifies the telephone number of the extension telephone of the emergency caller and the telephone number of the emergency call destination is busy A busy call disconnect / hold means for forcibly disconnecting or temporarily holding the busy call;
Emergency call information branch connection means for branching and connecting emergency call information between the extension telephone as the emergency call source and the emergency call destination to the predetermined key telephone.

A key telephone apparatus comprising a key telephone main unit accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones,
The key telephone is characterized by having display control means for displaying, on a display unit, an emergency call destination telephone number and an emergency call source telephone number received from the emergency notification means of the key telephone main unit.

Also, in a key telephone apparatus comprising a key telephone main unit accommodating an extension telephone including a plurality of central office lines and a plurality of single telephones and a plurality of key telephones,
Display control means for displaying the telephone number of the emergency call destination and the telephone number of the emergency call source received from the emergency notification means of the key telephone main device on a display unit,
An emergency call information notifying unit that loudspeaks and notifies the emergency call information branched by the emergency call information branch connection unit of the key telephone main unit.

[0024]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a main configuration of a key telephone apparatus of the present invention, FIG. 2 is a block diagram showing a configuration of a main control unit in FIG. 1, FIG. 3 is a diagram showing a configuration of a main storage unit in FIG. FIG. 5 is a sequence diagram showing an emergency call processing procedure of the present invention, and FIG. 5 is a flowchart showing an emergency call processing of the present invention.

As shown in FIG. 1, the key telephone apparatus 10 of the present invention comprises key telephones 20-1 and 20-2.
0-2, 20-3 and single phones 30-1, 30-2,
30-3 extension telephones and external lines 40-1, 40-2, 4
0-3 are accommodated.

The key telephone apparatus 10 includes an external line interface unit 11 and a key telephone interface unit 12.
, A single telephone interface unit 13 and a main control unit 14
And a main storage unit 15.

The external line interface unit 11 detects an incoming call,
It has the functions of closing, holding, and dialing a DC loop for an outside line.

The key telephone interface unit 12 supplies a call power to the key telephone via a communication line, transmits / receives a data signal via a signal line, supplies a control power, displays a lamp / LCD, controls a ring, and the like.

The single telephone interface unit 13 supplies a call power to the single telephone via a communication line, performs ring control, and the like.

As shown in FIG. 2, the main control unit 14 includes a telephone control unit 14-4 for controlling the entire key telephone apparatus, an external line control unit 14-5 for controlling connection with an external line, and a telephone control unit 14-. 4 and a speech line control unit 14-1 for controlling the extension line and the outside line communication line by receiving the speech line data from the outside line control unit 14-5, and a voice for receiving the speech data from the telephone control unit 14-4 and controlling the speech data. Data control unit 14-2
PBR control for converting a PB signal transmitted from a key telephone or a single telephone to data and transmitting the data to a telephone control unit 14-4, and converting a PB signal transmitted from an external line to data and transmitting the data to an external line control unit 14-5. 14-3.

As shown in FIG. 3, the main storage unit 15 stores software executed by the main control unit 14, various parameters associated with the execution of the software, storage means for system data, the state of external lines and telephones, and the emergency call destination. And an emergency call destination number storage unit 15-1 for registering the telephone number of the user, and an emergency call information when an emergency call is made to the emergency call destination registered in the emergency call destination number storage unit 15-1. And an emergency call information notification destination number storage unit 15-2 for registering an extension number for notification to each extension telephone.

Next, an embodiment of the present invention will be described with reference to the drawings. The emergency call processing will be described with reference to FIGS. Here, the person who discovered the fire that broke out in the factory was the nearest key telephone (20-
An example will be described in which a 119 is reported from 1) and a 119 is reported to the key telephone (20-2) of the fire brigade who is the fire manager of the extension and the key telephone (20-3) of the guard room. .

As shown in FIG. 3, emergency call destination numbers 110 and 119 are registered in the emergency call destination number storage section 15-1 of the main storage section 15 in advance. Also,
The emergency call information notification destination number storage unit 15-2 stores all the key telephones (20-1, 20-2, 20-3) and the single telephones (30-1, 20-1) accommodated in the key telephone device (main device) 10. 30-2, 30-3) The extension numbers of the key telephone (20-2) and the key telephone (20-3) in the guard room are registered in advance in correspondence with the respective fire officers. 3 shows the case of the key telephone 20-1.

First, the emergency call procedure will be described with reference to FIG. When the key telephone 20-1 performs an outside line capturing operation to detect a fire occurrence and notify the fire station of the fire occurrence,
As shown in FIG. 4, the outside line transmission event is generated by the key telephone interface unit 12, the telephone control unit 14-4, and the outside line control unit 1.
It is sent to the external line interface unit 11 via 4-5.

The telephone control unit 14-4, which has received the outside line transmission event, provides the telephone line control unit 14-1 with a telephone line for connecting the key telephone 20-1 and the telephone line of the external line (for example, 40-1). A connection event is transmitted, and the communication path control unit 14-1 connects the key telephone 20-1 to the communication path of the outside line 40-1.

Thereafter, the key telephones 20-1 to 119
When the number is dialed, the 119th dial event becomes the key telephone interface unit 1 in the same manner as the outside line calling event.
2. It is transmitted to the external line interface unit 11 via the telephone control unit 14-4 and the external line control unit 14-5.

Upon receiving the 119th dial event, the telephone control section 14-4 searches the emergency destination number storage section 15-1 of the main storage section 15 to determine whether or not the dial number 119 is registered. If the number 119 is registered, the emergency notification information notification destination number storage unit 1 of the main storage unit 15 is registered.
5-2, and searches for the emergency telephone information notification destination key telephone set 2 corresponding to the source key telephone set 20-1.
The extension numbers 0-2 and 20-3 are read, and an emergency call destination number and an emergency call source number display event are sent to the key telephones 20-2 and 20-3.
0-2 and 20-3 display the emergency destination number 119 and the button telephone number (emergency source number) of the emergency call on the display unit (for example, LCD) so that the fire commander and the guard can know where the fire occurred. Know.

When the key telephones 20-2 and 20-3 respond, the emergency telephone information between the key telephone 20-1 and the fire department can be monitored, so that the state of the fire spot can be known in detail, and fire extinguishing activities can be performed. Can be done quickly.

Next, the emergency call processing will be described in detail with reference to FIG. When an outside line transmission event occurs due to the outside line transmission capture operation of the key telephone 20-1 (step S101 in FIG. 5), the telephone control unit 14-4 of the main control unit 14
Instructs the call path control unit 14-1 to issue a call to the key telephone 20.
A call path is set between -1 and an outside line (for example, outside line 40-1) (S102).

When the telephone control unit 14-4 detects the emergency call destination number (119) dialed from the key telephone 20-1 after setting the communication path (S103), the main storage unit 15
The emergency calling number stored in the emergency calling number storage unit 15-1 is compared with the registered emergency calling number, and if they match, it is determined that the call is an emergency call, and if they do not match, the call is a general call. (S104).

If it is determined in step S104 that the call is a general call, the communication path with the destination is connected (S105), the destination is called, and a response from the destination is detected (S10).
6) The communication state is set (S107), and when the end of the call is detected (S108), the call processing of the general call ends.

If the emergency call destination number dialed by the key telephone 20-1 is registered in the emergency call destination number storage unit 15-1 and the determination in step S104 is an emergency call, the communication path with the emergency call destination is determined. Is connected (S109), the emergency call destination is called, and when the response of the emergency call destination is detected (S1).
10) The state becomes the emergency call state (S111), and when the emergency call ends (S112), the emergency call processing ends.

The telephone control section 14-4 connects the communication path with the emergency call destination (S109), and at the same time, searches the emergency call information notification destination number storage section 15-2, and searches the key telephone 20-1 as the emergency call source. Key telephone 20-2, which is the notification destination of the emergency call information registered corresponding to the extension number of
The extension number of 20-3 is read (S113), and the emergency telephone number (119) is transmitted to the key telephones 20-2 and 20-3.
No.) and the display control information of the extension number of the emergency caller button telephone 20-1.

Each of the firefighter's key telephone 20-2 and the guard room 20-3 has an emergency call destination number (119) and an emergency call on its own display unit according to the display control information received from the telephone control 14-4. Yuan key telephone 20-
The extension number 1 is displayed (S114).

The telephone control section 14-4 controls the key telephone 2
It is determined whether 0-2 or 20-3 is busy (S11).
5) Connect a voice path between the key telephone 20-1 and the key telephones 20-2 and 20-3 (S11).
7). When the captain of the fire brigade or the person in charge of the guard room leaves, transfer registration is made and the key telephone 20-2 or 20
When -3 is not answered, an audio path may be connected to the registered key telephone.

If it is determined in step S115 that the call is busy, a predetermined message previously stored in a message storage unit (not shown), for example, "call is disconnected for emergency" is sent to the other party who is busy. After the transmission, the busy call is disconnected (S116), and the voice path is connected.

Instead of forcibly disconnecting the busy call, a message "Temporary hold for emergency" may be sent out to temporarily hold the busy call.

The fire brigade captain of the key telephone 20-2 and the guard of the key telephone 20-3 provide the emergency destination number (119).
And confirming the display of the extension number of the emergency call source key telephone 20-1 (S118), and then responding to the emergency call (fire) made between the emergency call source key telephone 20-1 and the emergency call destination fire station. Occurrence report) can be monitored (S119).

As described above, the fire discoverer can send a 119 call to the fire department from the nearest key telephone or a single telephone to report the fire situation, and to the firefighter or the guard room in the confusion during the fire. Communication is no longer necessary, and fire finder can concentrate on fire fighting.

Also, the fire commander or guard can know the fire occurrence and the location of the fire from the emergency call destination telephone number and the emergency call source telephone number displayed on his / her key telephone. By monitoring the emergency call between the caller and the emergency callee, the situation at the fire site can be known in detail, and fire extinguishing activities can be quickly and accurately commanded.

[0051]

As described above, the key telephone apparatus of the present invention compares an outgoing number with a pre-registered emergency destination number, determines that the call is an emergency outgoing call, and performs a predetermined emergency outgoing call process. Execute and connect the emergency caller and the emergency callee to enable an emergency call, and at the same time, send the telephone number of the caller and the emergency callee to a predetermined extension telephone registered in advance corresponding to the emergency caller telephone. Display phone number and
Also, since the emergency call source telephone and a plurality of predetermined extension telephones are connected by a voice path, and the emergency call source is configured to branch and connect the emergency call information performed with the emergency call destination to the predetermined extension telephone, The fire discoverer can send a 119 call to the fire department from the nearest key phone or a single phone to report the fire situation, but there is no need to contact the fire commander or guard room during the confusion during the fire. Can concentrate on fire fighting.

Also, the fire commander or guard can know the fire occurrence and the location of the fire from the emergency call destination telephone number and the emergency call source telephone number displayed on his / her key telephone. By monitoring the emergency call between the caller and the emergency callee, the situation at the fire site can be known in detail, and fire extinguishing activities can be quickly and accurately commanded.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main configuration of a key telephone apparatus of the present invention.

FIG. 2 is a block diagram showing a configuration of a main control unit of the key telephone apparatus of the present invention.

FIG. 3 is a block diagram showing a configuration of a main storage unit of the key telephone apparatus of the present invention.

FIG. 4 is a sequence diagram showing an emergency call processing procedure of the key telephone apparatus of the present invention.

FIG. 5 is a flowchart showing an emergency calling process of the key telephone apparatus of the present invention.

[Explanation of symbols]

 Reference Signs List 10 key telephone device 11 external line interface unit 12 key telephone interface unit 13 single telephone interface unit 14 main control unit 14-1 speech channel control unit 14-2 voice data control unit 14-3 PBR control unit 14-4 telephone control unit 14- 5 External line control unit 15 Main storage unit 15-1 Emergency call destination number storage unit 15-2 Emergency call information notification destination number storage unit 20-1 Button telephone 20-2 Button telephone 20-3 Button telephone 30-1 Single telephone 30- 2 Single phone 30-3 Single phone 40-1 Outside line 40-2 Outside line 40-3 Outside line

Claims (7)

[Claims] 1. A key telephone apparatus comprising: a key telephone apparatus accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones, wherein the key telephone main apparatus comprises: When an emergency call is made from the extension telephone to a predetermined emergency destination, the mobile telephone has emergency notification means for notifying the telephone number of the extension telephone as the emergency source and the telephone number of the emergency destination to the predetermined key telephone. Button telephone equipment to do. 2. A key telephone apparatus comprising: a key telephone apparatus accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones, wherein the key telephone main apparatus comprises: A button telephone having emergency call information branch connection means for making an emergency call from an extension telephone to a predetermined emergency call destination and branching and connecting emergency call information to and from said emergency call destination to said predetermined key telephone; apparatus. 3. A key telephone apparatus comprising a key telephone apparatus accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones, wherein the key telephone main apparatus comprises: When an emergency call is made from the extension telephone to a predetermined emergency destination, an emergency notification means for notifying the telephone number of the extension telephone serving as the emergency source and the telephone number of the emergency destination to the predetermined key telephone; A button telephone device comprising: emergency call information branch connection means for branch connection of emergency call information performed between a certain extension telephone and the emergency call destination to a predetermined key telephone. 4. A key telephone apparatus comprising: a key telephone apparatus accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones, wherein the key telephone apparatus is the extension telephone. An emergency call destination number storage unit for registering a plurality of emergency call destination telephone numbers corresponding to each; and an emergency call destination number storage unit when an emergency call is made from any of the extension telephones to a predetermined emergency call destination. Outgoing call determining means for detecting the presence or absence of registration of the telephone number of the emergency call destination, determining that the call is a general call when there is no registration, and determining an emergency call when there is registration, Emergency notification means for notifying the telephone number of the extension telephone of the emergency call source and the telephone number of the emergency call destination to the predetermined key telephone, and performing the emergency call between the extension telephone and the emergency call destination Emergency call information branch connection means for branching and connecting emergency call information to the predetermined key telephone. 5. A key telephone apparatus comprising a key telephone apparatus accommodating an extension telephone including a plurality of central office lines, a plurality of single telephones, and a plurality of key telephones, wherein the key telephone main apparatus is the extension telephone. An emergency call destination number storage unit for registering a plurality of emergency call destination telephone numbers corresponding to each; and an emergency call destination number storage unit when an emergency call is made from any of the extension telephones to a predetermined emergency call destination. Outgoing call determining means for detecting the presence or absence of registration of the telephone number of the emergency call destination, determining that the call is a general call when there is no registration, and determining an emergency call when there is registration, Emergency notification means for notifying the telephone number of the extension telephone of the emergency caller and the telephone number of the emergency call destination to the predetermined key telephone; and wherein the emergency notification means is provided with the telephone number of the extension telephone of the emergency caller. A busy call disconnection / holding means for forcibly disconnecting or temporarily holding the busy call when the predetermined key telephone which has notified the telephone number of the emergency call destination is busy, the extension telephone which is the emergency call source, and An emergency call information branch connection means for branching and connecting emergency call information to and from an emergency call destination to the predetermined key telephone. 6. A key telephone apparatus comprising: a key telephone apparatus accommodating an extension telephone including a plurality of office lines, a plurality of single telephones, and a plurality of key telephones, wherein the key telephone is the key telephone apparatus. 6. A key telephone according to claim 1, further comprising display control means for displaying a telephone number of an emergency call destination and a telephone number of an emergency call source received from said emergency notification means on a display unit. apparatus. 7. A key telephone apparatus comprising: a key telephone apparatus accommodating an extension telephone including a plurality of office lines and a plurality of single telephones and a plurality of key telephones, wherein the key telephone is the key telephone main apparatus. Display control means for displaying the telephone number of the emergency call destination and the telephone number of the emergency call source received from the emergency notifying means on the display unit, and the emergency call information branch connection means of the key telephone main unit. 7. The key telephone apparatus according to claim 1, further comprising: an emergency call information notifying unit that audibly notifies the emergency call information.