JP7813864B2 - Fire alarm system - Google Patents

Description

The present invention relates to a fire alarm system that connects a telephone base unit and a telephone handset via a transmission line that connects a fire detector from a receiver and a telephone line.

Conventionally, in fire alarm systems known as R-type, a terminal device such as a fire detector with transmission capabilities is connected to a transmission line drawn from the receiver. When a fire is detected, for example, based on a fire interrupt from the fire detector, a search command is issued to identify the address of the fire detector that triggered the alarm, the address where the fire occurred is displayed, and fire data is collected and monitored from the identified fire detector.

In this way, knowing the address of the fire detector that detected the fire enables appropriate evacuation guidance and firefighting activities, making this a particularly essential function for fire monitoring in large-scale facilities.

In addition, in fire alarm systems, a telephone base unit is installed in the receiver as an emergency communication device, and a telephone jack installed in the transmitter, etc. is connected to a telephone line drawn from the receiver into the alert area.In the event of a fire or during inspection, when the maintenance telephone handset carried by the person in charge is connected to the telephone jack of the transmitter, etc., a call is made on the receiver, and a call connection with the maintenance telephone handset can be established by off-hooking the telephone base unit.

In addition, emergency telephone equipment may also be installed as related equipment to fire alarm equipment. Emergency telephone equipment consists of an emergency telephone panel with a telephone base unit installed in the same location as the receiver, and telephone and control lines are drawn from the emergency telephone panel to the restricted area, where an emergency telephone handset is connected.

The maintenance telephone equipment for fire alarm systems does not allow the parent telephone unit to call a specific maintenance telephone handset, but the emergency telephone equipment allows the emergency telephone handset to be called by calling a specific telephone number from the emergency telephone panel, making it possible to use calls not only in emergencies such as fires, but also for day-to-day maintenance and management of the equipment.

Japanese Patent Application Laid-Open No. 2004-064709 JP 2017-004451 A JP 2016-076064 A Japanese Patent Application Laid-Open No. 2017-068523 Japanese Patent Application Publication No. 10-69591

However, conventional emergency telephone equipment that can call specific telephone handsets must be installed as part of the fire alarm system, which increases the cost of the equipment. On the other hand, maintenance telephone equipment for fire alarm systems, which connects a maintenance handset to a telephone jack on the telephone line and then connects to the base unit, requires less equipment cost, but does not allow for advanced call control such as calling specific telephone handsets, making it less convenient than emergency telephone equipment.

The objective of this invention is to provide a fire alarm system that utilizes the transmission function used in R-type fire alarm systems to provide advanced call control, including calling a specific telephone handset, as well as a highly convenient call function that allows calls to be made by connecting a telephone handset to a telephone jack.

(Fire alarm system 1 equipped with first and second telephone systems)
The present invention comprises a transmission line connecting a terminal device including a telephone repeater located in a security zone to a receiver;
a first telephone line connecting the telephone repeater and the receiver;
a second telephone line connecting the receiver to a telephone jack located in the security zone;
A fire alarm system equipped with
The receiver stores address information that can identify the telephone repeater, and is capable of making a call connection with a first telephone handset connected to a first telephone line via the telephone repeater and a second telephone handset connected to a second telephone line via a telephone jack;
The receiver and the first handset are connected to each other by controlling the transmission and reception of a predetermined call control signal via a transmission line between the receiver and a telephone repeater to which the first handset is connected,
The receiver and the second handset are connected to each other by connecting the second handset to a telephone jack.
When an incoming call is received from the first handset, a display indicating that an incoming call has been received is displayed in a manner that enables identification of the first handset that is the source of the incoming call, based on address information of a telephone repeater to which the first handset that is the source of the incoming call is connected;
When an incoming call is received from the second handset, a notification is made to indicate that an incoming call has been received from the second handset.

(Fire alarm system 2 equipped with first and second telephone systems)
In another embodiment of the present invention, a transmission line connecting a terminal device including a telephone repeater located in a security zone and a receiver;
a first telephone line connecting the telephone repeater and the receiver;
a second telephone line connecting a second telephone handset located in the security zone to the receiver;
A fire alarm system equipped with
the receiver stores address information that can identify the telephone repeater, and is capable of making a call connection with a first telephone handset connected to the first telephone line and a second telephone handset connected to the second telephone line via the telephone repeater;
The receiver and the first handset are connected to be able to communicate with each other by controlling the transmission and reception of a predetermined call control signal via a transmission line between the receiver and a telephone repeater to which the first handset is connected,
the receiver and the second handset are connected to be able to communicate when the receiver detects an electrical change in the second telephone line accompanying a call start request operation using the second handset;
When an incoming call is received from the first handset, a display indicating that an incoming call has been received is displayed in a manner that enables identification of the first handset that is the source of the incoming call, based on address information of a telephone repeater to which the first handset that is the source of the incoming call is connected;
When an incoming call is received from the second handset, a notification is made to indicate that an incoming call has been received from the second handset.

(Output of ring tone from second handset)
The notification that an incoming call has been received from the second handset is made by outputting a second handset ring tone that indicates that an incoming call has been received from the second handset.

(Effectiveness of fire alarm systems)
The present invention is a fire alarm system in which a terminal device including a telephone repeater is connected to a transmission line drawn from a receiver into a security zone, and the telephone repeater is connected to a telephone line also drawn from the receiver into the security zone and to which a telephone jack is connected. The receiver is capable of making a call connection with a first telephone handset connected to the telephone line via the telephone repeater, and a second telephone handset connected to the telephone line via the telephone jack. The call connection with the first telephone handset is controlled by sending and receiving a predetermined call control signal via the transmission line between the receiver and the telephone repeater to which the first telephone handset is connected. The call connection with the second telephone handset is controlled by the connection status of the second telephone handset to the telephone jack. If a connection of the second telephone handset to a telephone jack is detected during a call connection with the first telephone handset, the call connection with the second telephone handset is switched to. Therefore, by utilizing the transmission function of the transmission line used in R-type fire alarm systems for call control, advanced call control, including calls specifying the first telephone handset, can be achieved simply and at low cost.

In addition to advanced call control, including calling a specific first telephone handset using a transmission line, it is also possible to make calls by connecting a second telephone handset to a telephone jack without compromising the functionality of the first telephone handset, providing even greater convenience.

Furthermore, if a second handset is connected to the telephone jack while a call is in progress between the base unit and the first handset, the previous call connection between the base unit and the first handset is put on hold, allowing the call with the second handset to take priority.

(Effectiveness of fire alarm systems equipped with emergency telephone equipment and maintenance telephone equipment)
In another aspect of the present invention, there is provided a fire alarm system including a transmission line drawn from a receiver to a security zone and connected to a terminal device including a telephone repeater, a first telephone line drawn from the receiver to the security zone and connected to the telephone repeater, and a second telephone line drawn from the receiver to the security zone and connected to a telephone jack, wherein the receiver stores address information for identifying the telephone repeater, and is capable of establishing a call connection with a first telephone handset connected to the first telephone line via the telephone repeater and a second telephone handset connected to the second telephone line via the telephone jack, and the call connection with the first telephone handset is controlled by sending and receiving a predetermined call control signal via the transmission line between the receiver and the telephone repeater to which the first telephone handset is connected, and the call connection with the second .... is controlled by the connection status of the second telephone handset to the telephone jack, and when an incoming call is received from the first telephone handset, a display indicating that an incoming call has occurred is displayed so that the first telephone handset that is the call source can be identified based on the address information of the telephone repeater to which the first telephone handset is connected, and when an incoming call is received from the second telephone handset, an announcement is made indicating that an incoming call has occurred from the second telephone handset.As a result, for the first telephone equipment using the first telephone line, calls can be made by sending and receiving a specified call control signal via the transmission line, and for the second telephone equipment using the second telephone line, calls can be made by connecting the second telephone handset to the telephone jack, making it possible to use both the first telephone equipment and the second telephone equipment, and further improving convenience.

In addition, by integrating the functions of the base unit devices for the first and second telephone equipment into the receiver, the installation space for the fire alarm equipment and telephone equipment is reduced.Furthermore, calls with the first telephone handset or the second telephone handset can be made using the same base unit, making call operations simple and easy without having to change locations.

FIG. 1 is an explanatory diagram showing an embodiment of a fire alarm system having a call control function. FIG. 2 is a block diagram illustrating an embodiment of the telephone repeater of FIG. 1. FIG. 2 is a block diagram showing an embodiment of a telephone base unit circuit section and a call detection circuit section provided in the receiver of FIG. 1. A time chart showing call control in which a telephone base unit calls a designated telephone handset. Time chart showing call control with the base unit when the handset is off-hook A time chart showing call control when a handset goes off-hook while the base unit is in a call with another handset. A time chart showing call control when a call is received from another handset during a call between the base unit and the handset and the call is switched over. Time chart showing call control for three-way calls between a base station and two handsets A time chart showing call control performed by connecting a maintenance telephone handset to a telephone jack. An explanatory diagram showing an embodiment of a fire alarm system equipped with a call control function for emergency telephone equipment linked to emergency broadcast equipment and maintenance telephone equipment used for maintenance and inspection.

[Fire alarm system]
(Outline of fire alarm system with call control function)
The fire alarm system is equipped with a call control function, and a receiver 10, such as an R-type receiver, is installed in a building manager's office on the first floor of the building. Transmission lines 12a and 12b and telephone lines 16a and 16b are extended from the receiver 10 to the alert area.

Transmission lines 12a and 12b are connected to multiple fire detectors 14 and repeaters 15, each with a transmission function and assigned a unique address. Furthermore, transmission lines 12a and 12b and telephone lines 16a and 16b are connected to multiple telephone repeaters 18, each equipped with a telephone handset 20. Each telephone repeater 18 is assigned a unique address and has transmission and call control functions. Furthermore, receiver 10 is provided with a telephone base unit 28 corresponding to each telephone handset 20. Furthermore, telephone lines 16a and 16b ensure transmission quality for audio signals in the audio frequency band of 300 to 3400 Hz, which is the audible band.

Here, the maximum number of addresses that can be set for the fire detectors 14, repeaters 15, and telephone repeaters 18 connected to the transmission lines 12a and 12b is, for example, 255, and a maximum of 255 terminal devices, including fire detectors 14, repeaters 15, and telephone repeaters 18, can be connected to the transmission lines 12a and 12b.

Transmitter 36 is connected to repeater 15. Transmitter 36 is equipped with transmitter button 36a. When transmitter button 36a is pressed to turn it on in the event of a fire, a transmission signal is output to repeater 15. A fire notification signal is then sent from repeater 15 to receiver 10 via transmission lines 12a and 12b, and a fire alarm is output.

The transmitter 36 is also provided with a telephone jack 38, which is connected to the telephone lines 16a and 16b. When the plug 42 of the maintenance telephone handset 40 carried by the person in charge is inserted into the telephone jack 38, the maintenance telephone handset 40 is connected to the telephone lines 16a and 16b, and a call connection is established with the telephone base unit 28 provided in the receiver 10, allowing the call to be made.

(Receiver functional configuration)
The receiver 10 includes a receiving control unit 22, a transmission unit 24, a telephone base unit circuit unit 26, a telephone base unit 28, a display 30 with a touch panel, a display unit 31, an operation unit 32, an alarm unit 33 with a speaker, a notification unit 34, and a call detection circuit unit 35.

The reception control unit 22 is a computer circuit equipped with a CPU, memory, various input/output ports, etc. The transmission unit 24 transmits and receives signals according to a predetermined communication protocol between the fire detector 14, repeater 15, or telephone repeater 18 connected to the transmission lines 12a and 12b.

Downstream signals from the transmission unit 24 to the fire detector 14, repeater 15, or telephone repeater 18 are transmitted in voltage mode. These voltage mode signals are transmitted as voltage pulses that change the line voltage of the transmission lines 12a and 12b, for example, between 18 volts and 30 volts.

In contrast, upstream signals from the fire detector 14, repeater 15, or telephone repeater 18 to the receiver 10 are transmitted in current mode. In this current mode, a signal current flows through the transmission lines 12a and 12b at the timing of bit 1 of the transmission data, and the upstream signal is transmitted to the receiver as a so-called current pulse train.

(Fire Monitoring and Control Department)
The reception control unit 22 of the receiver 10 is provided with the function of a fire monitoring control unit 44 as a function realized by the execution of a program by the CPU.

During normal monitoring, the fire monitoring control unit 44 periodically instructs the transmission unit 24 to send a broadcast batch AD conversion signal containing a batch AD conversion command. Fire detectors 14 that receive this batch AD conversion signal detect and store the smoke density or temperature as sensor data, and the repeater 15 detects and stores the transmitter signal at that time. The fire monitoring control unit 44 then transmits a call signal containing a polling command that sequentially specifies terminal addresses.

When the fire detector 14 receives a call signal with an address that matches its own address, it transmits a response signal containing the sensor data it is holding at the time to the receiver 10. Furthermore, when the fire detector 14 detects a fire, it transmits a fire interrupt signal to the receiver 10.

When the repeater 15 receives a call signal with an address that matches its own address, it transmits a response signal including the transmitter signal it is holding at that time to the receiver 10. Furthermore, when the repeater 15 receives a transmitter signal that has been turned on by pressing the transmitter button 36a of the transmitter 36, it transmits a fire interrupt signal to the receiver 10 as a fire notification signal, just like the fire detector 14.

When the fire monitoring control unit 44 receives a fire interrupt signal via the transmission unit 24, it sends a group search command signal to identify the group containing the fire detector 14 and repeater 15 that detected the fire, then sends an intra-group search command signal to identify the address of the fire detector 14 or repeater 15 that detected the fire, outputs a fire alarm, and displays the fire occurrence address or transmitter address, and then controls the collection and monitoring of fire data from the identified fire detector 14 or repeater 15.

(Telephone base unit control unit)
The reception control unit 22 of the receiver 10 is provided with the function of a telephone base unit control unit 46 as a function realized by the execution of a program by the CPU.

The telephone base unit control unit 46 instructs the transmission unit 24 to send and receive command signals required for various call controls between the telephone repeater 18 via transmission lines 12a and 12b, and controls call connection and call disconnection between the telephone base unit 28 and the telephone handset 20 via telephone lines 16a and 16b.

The call control by the telephone base unit control unit 46 of this embodiment includes the following.
(1) Call control by calling a designated telephone handset.
(2) Call control by calling from a telephone handset.
(3) Call switching control when a call is made from another handset while a call is being made with another handset.
(4) Three-way call control between a telephone base unit and two telephone handsets.
(5) Call control by connecting a maintenance telephone handset to a telephone jack.

Of these, call control (1) to (4) uses command signals such as a call command signal, an incoming call response command signal, a hold command signal, and a busy command signal. A call command signal is a signal that requests a call from the handset. A call response command signal is a signal that is sent when the handset goes off-hook upon receiving a call command signal. A hold command signal is a signal that instructs the handset to output a hold tone. A busy command signal is a signal that instructs the handset to output a busy tone. Details of communication control using these command signals will be explained later.

(Call detection circuit section)
When the plug 42 of the maintenance telephone handset 40 is inserted into the telephone jack 38 of the transmitter 36 and connected to the telephone lines 16a, 16b, a line current flows. The call detection circuit unit 35 provided in the receiver 10 detects this line current and outputs a call detection signal to the receiving control unit 22.

When the telephone base unit control unit 46 provided in the reception control unit 22 receives a call detection signal from the call detection circuit unit 35, it outputs a ring tone from the speaker of the alarm unit 33 based on the call connection of the maintenance telephone handset 40. When the person in charge hears this and picks up the telephone base unit 28, the telephone base unit circuit unit 26 connects the telephone base unit 28 to the telephone lines 16a and 16b based on the detection of the telephone base unit 28 being off-hook, and controls the establishment of a call connection with the maintenance telephone handset 40.

[Configuration of telephone repeater]
Fig. 2 is a block diagram showing an embodiment of the telephone repeater of Fig. 1. As shown in Fig. 2, the circuit section of the telephone repeater 18 is provided with a telephone handset control section 48 and a transmission section 50 as the circuit section on the transmission lines 12a and 12b side, and is provided with a connection switching section 52, a control sound generating section 54, a pair of switch circuits 56, a transformer 58, a hook switch 60, and a speaker 61 as the circuit section on the telephone lines 16a and 16b side, and the telephone handset 20 is provided with a receiver 45 and a transmitter 47.

The telephone handset control unit 48 is composed of a computer circuit equipped with a CPU, memory, various input/output ports, etc., and the functions of the telephone handset control unit 48 are realized by the CPU executing a program.

The telephone handset control unit 48 of this embodiment controls the following calls.
(1) Call control by calling the telephone base unit.
(2) Call control by calling from the telephone base unit.
(3) Call switching control by calling the base unit during a call with another handset.
(4) Three-way call control between a telephone base unit and two telephone handsets.

In these call controls, command signals such as a call command signal, an incoming call response command signal, a hold command signal, and a call in progress command signal are used, and details of call control will be explained later.

The transmission unit 50 transmits and receives various command signals required for call control via transmission lines 12a and 12b to and from the transmission unit 24 of the receiver 10 shown in Figure 1, in accordance with the same communication protocol as in the case of fire monitoring. Furthermore, the transmission unit 50 receives downstream signals from the receiver 10 in voltage mode, and transmits upstream signals to the receiver 10 in current mode.

The connection switching unit 52 operates in response to instructions from the telephone handset control unit 48 to turn on and off the switch circuit unit 56, which uses relay contacts, semiconductor switch elements, etc., to connect and disconnect the telephone handset 20 to and from the telephone lines 16a and 16b.

The control sound generation unit 54 operates in response to instructions from the telephone handset control unit 48, generating audio signals such as predetermined line connection sounds, ring tones for the telephone base unit, hold tones, and busy tones, and outputs these to the transmitter 47 of the telephone handset 20. It also generates audio signals for ring tones in response to calls from the telephone base unit and outputs these to the speaker 61.

The primary winding of the transformer 58 is connected to the telephone lines 16a and 16b, and the secondary winding is connected to the handset 45. Only the AC audio signals from the telephone lines 16a and 16b, on which a predetermined DC voltage is superimposed, are picked up and amplified by the handset 45, and feedback is also prevented. The transmitter 47 of the telephone handset 20 is connected to the telephone lines 16a and 16b.

The hook switch 60 detects whether the telephone handset 20 is off-hook or on-hook and outputs an off-hook detection signal or an on-hook detection signal to the telephone handset control unit 48.

Note that the telephone circuitry on the telephone lines 16a and 16b in Figure 2 shows a basic analog telephone circuit, but is not limited to this; an audio amplifier may be provided as needed, and the circuit may also be a digital telephone circuit that receives digital audio signals, converts them from digital to analog, outputs them to the receiver 45, and converts audio signals from the transmitter 47 from digital to digital and transmits them.

[Configuration of the telephone base unit circuit section and call detection circuit section of the receiver]
FIG. 3 is a block diagram showing an embodiment of the telephone base unit circuit section and the call detection circuit section provided in the receiver of FIG.

(telephone base unit circuit section)
3, the telephone base unit circuit section 26 is provided with a connection switching section 62, a control sound generating section 64, a pair of switch circuits 66, a transformer 68, and a hook switch 70, and the telephone base unit 28 is provided with a receiver 72 and a transmitter 74. A telephone line voltage Vt of, for example, DC 48 V is applied from the telephone base unit circuit section 26 between the telephone lines 16a and 16b.

The connection switching unit 62 operates in response to instructions from the telephone base unit control unit 46 in Figure 1 to turn the switch circuit unit 66 on and off, connecting and disconnecting the telephone base unit 28 to the telephone lines 16a and 16b.

The control sound generation unit 64 operates in response to instructions from the telephone base unit control unit 46, generating audio signals such as a predetermined line connection sound, a ring tone indicating a call to the telephone handset 20, a hold tone, and a busy tone, and outputs these to the handset 72 of the telephone base unit 28. It also generates an audio signal for a ring tone in response to a call from the telephone handset 20 or the maintenance telephone handset 40, and outputs this to a speaker provided in the alarm unit 33, for example.

The transformer 68 connects its primary winding to the telephone lines 16a and 16b, and its secondary winding to a handset 72. Only the AC audio signals from the telephone lines 16a and 16b, on which a predetermined telephone line voltage Vt is superimposed, are picked up by the handset 72 and amplified, while also preventing feedback. The transmitter 74 of the telephone base unit 28 is connected to the telephone lines 16a and 16b.

The hook switch 70 detects whether the telephone base unit 28 is off-hook or on-hook and outputs an off-hook detection signal or an on-hook detection signal to the telephone base unit control unit 46.

Note that the telephone circuit on the telephone lines 16a and 16b in Figure 3 shows a basic analog telephone circuit, similar to the telephone repeater 18 in Figure 2, but is not limited to this and may include an audio amplifier as needed, or may even be a digital telephone circuit.

(Call detection circuit section)
As shown in FIG. 3, in the call detection circuit unit 35, resistors 76, 78, and 80 are connected in series between the telephone line 16a, to which a predetermined line voltage Vt is applied, and the negative telephone line 16b, and the telephone line 16a is drawn out from between the resistors 76 and 78 to the terminal side, and a call detection signal is taken out from between the resistors 78 and 80 and output to the reception control unit 22.

As shown in Figure 1, when the plug 42 of the maintenance telephone handset 40 is inserted into the telephone jack 38 of the transmitter 36 and the maintenance telephone handset 40 is connected between the telephone lines 16a and 16b, the maintenance telephone handset 40 also has a telephone circuit equipped with a transformer, handset, and transmitter, just like the telephone handset 20 shown in Figure 2 or the telephone base unit 28 shown in Figure 3. Therefore, when the transmitter is connected between the telephone lines 16a and 16b via the transformer primary winding, a predetermined line current flows.

The line current associated with connecting this maintenance telephone 40 to the telephone jack 38 flows to the telephone line 16a via resistor 76 in the call detection circuit section 35 shown in Figure 3. This reduces the line voltage by the amount of the voltage drop across resistor 76, and the detection voltage output as the call detection signal divided by resistors 78 and 80 also decreases. The telephone base unit control section 46 of the receiving control section 22 determines that the maintenance telephone handset 40 is connected based on the drop in the level of the call detection signal, and outputs a ring tone and displays a message on the screen indicating that the maintenance telephone handset 40 is being called.

[Call control between the telephone base unit and the telephone handset]
(Designated call to a handset by a base unit)
FIG. 4 is a time chart showing call control in which a telephone base unit calls a designated telephone handset, and the control operation is performed by the telephone base unit control unit 46 of the receiver 10 shown in FIG. 1 and the telephone handset control unit 48 of the telephone repeater 18 shown in FIG. 2.

When a person in charge picks up the telephone base unit 28 to contact another person in the security zone, an off-hook detection signal is output from the hook switch 70. As shown in Figure 4, the telephone base unit control unit 46 determines in step S1 that the telephone base unit 28 is off-hook and proceeds to step S2, where it displays a handset call screen on the display 30 and simultaneously instructs the control sound generation unit 64 to output a line connection sound, such as a continuous "beep," from the handset 72 of the telephone base unit 28.

The handset call screen displayed on the display 30 in step S2 displays key buttons arranged as 0, 1-9, #, and *. When a handset call operation is performed by touching the telephone number of the telephone handset to be called, the telephone base unit control unit 46 recognizes the handset call operation in step S3 and proceeds to step S4, instructing the transmission unit 24 to send a call command signal specifying the repeater address corresponding to the called telephone number to the transmission lines 12a and 12b. At this time, a ring tone is output from the telephone base unit 28 to the telephone handset.

When the telephone handset control unit 48 of the telephone repeater 18 receives a call command signal specifying its own address from the transmission unit 50 via the transmission lines 12a and 12b, in step S5 it instructs the control sound generation unit 54 to make a call by outputting a ring tone from the speaker 61.

When the person on-site picks up the telephone handset 20 in response to this call, an off-hook detection signal from the hook switch 60 determines that the telephone is off-hook in step S6, and in step S7 the transmission unit 50 is instructed to send a call response command signal including the telephone's own address to the receiver 10 via transmission lines 12a and 12b. Next, in step S8 the connection switching unit 52 is instructed to turn on the switch circuit unit 56, establishing a call connection by connecting the telephone circuit unit on the telephone handset 20 side to telephone lines 16a and 16b.

When the telephone base unit control unit 46 of the receiver 10 receives the incoming call response command signal transmitted from the telephone repeater 18 in step S7, it stops outputting the ring tone to the telephone handset 20, and in step S9 instructs the connection switching unit 62 to turn on the switch circuit unit 66, thereby establishing a call connection between the telephone base unit circuit unit 26 of the telephone base unit 28 and the telephone lines 16a and 16b.

This connects the base unit 28 and the called handset 20 to the telephone lines 16a and 16b, allowing the call to be conducted. When the call ends, the base unit 28 and handset 20 are returned, and an on-hook state is determined in step S10 or S12. Then, in step S11 or S13, the call is disconnected from the telephone lines 16a and 16b, and the call ends.

(Calling the base unit by a handset)
5 is a time chart showing call control for calling the base unit from the handset. When a person in the security zone picks up the handset 20 to contact the receiver 10, an off-hook detection signal is output from the hook switch 60. As shown in FIG. 5, the handset control unit 48 determines in step S21 that the handset 20 is off-hook, proceeds to step S22, and instructs the control sound generation unit 54 to output a line connection sound, which is a continuous sound such as a "beep," from the receiver 45 of the handset 20.

Next, in step S23, the telephone handset control unit 48 instructs the transmission unit 50 to transmit a call command signal including its own address to the receiver 10 via the transmission lines 12a and 12b. At this time, the telephone handset 20 outputs a ring tone to the telephone base unit 28.

When the telephone base unit control unit 46 of the receiver 10 receives a call command signal including the repeater address from the transmission unit 50 via the transmission lines 12a and 12b, it instructs the alarm unit 33 to output a ring tone from the speaker in step S24 to initiate a call, and then proceeds to step S25 to display a handset call screen on the display 30, displaying the telephone number of the handset being called, etc.

When the person in charge picks up the telephone base unit 28 installed on the receiver 10 in response to the ring tone in step S24, the telephone base unit control unit 46 determines in step S26 that the telephone base unit 28 is off-hook, instructs the transmission unit 24 in step S27 to send a call response command signal specifying the repeater address that made the call to the transmission lines 12a, 12b, and in step S28 instructs the connection switching unit 62 to turn on the switch circuit unit 66, thereby connecting the telephone base unit 28 to the telephone lines 16a, 16b for communication.

On the other hand, when the telephone handset control unit 48 receives the call response command signal specifying its own address transmitted from the receiver 10 in step S27, it stops the ring tone to the telephone base unit 28 and proceeds to step S29, where it instructs the connection switching unit 52 to turn on the switch circuit unit 56, thereby connecting the telephone handset 20 to the telephone lines 16a and 16b for communication.

This connects the telephone handset 20 and the called telephone base unit 28 to the telephone lines 16a and 16b, allowing the call to be conducted. When the call ends, the telephone handset 20 and the telephone base unit 28 are returned, and an on-hook state is determined in step S30 or S32. Then, in step S31 or S33, the call is disconnected from the telephone lines 16a and 16b, and the call connection is terminated.

(Calling a handset while the base unit is busy)
FIG. 6 is a time chart showing call control when a handset goes off-hook during a call between the base unit and another handset.

Assume that during a call from the base station shown in Figure 4 or a call from the handset shown in Figure 5, as shown in Figure 6, the handset control unit 48 of another telephone repeater 18 determines in step S41 that the handset 20 is off-hook, outputs a line connection sound from the handset 20 in step S42, and then sends a call command signal including its own address to the receiver 10 via the transmission lines 12a and 12b in step S43, causing a ring tone to be output from the speaker of the alarm unit 33.

In this case, the telephone base unit control unit 46 of the receiver 10 receives the call command signal transmitted from the telephone repeater 18 in step S43, but determines in step S44 that a call with another telephone handset is in progress. In step S45, the display 30 displays a new handset call on the handset call screen, and then in step S46 transmits a call-in-progress command signal specifying the address of the telephone repeater 18 that transmitted the call command signal to the transmission lines 12a and 12b.

When the telephone handset control unit 48 of the telephone repeater 18 receives a call-in-progress command signal specifying its own address via the transmission lines 12a and 12b, in step S47 it instructs the control sound generation unit 54 to output a predetermined call-in-progress sound from the receiver 45 of the telephone handset 20.

As a result, the person who picked up the telephone handset 20 realized that the telephone base unit 28 was in use and replaced the telephone handset 20, and the telephone handset control unit 48 determined that the telephone handset was on-hook in step S48 and terminated the call connection.

(Call switching due to a call from another handset during a call between the base unit and handset)
7 is a time chart showing call control when a call is received from another handset during a call between the base unit and the handset, and the call is switched over. Here, the telephone repeater 18 that made the first call is called telephone repeater 18-1, the telephone repeater 18 that made the second call is called telephone repeater 18-2, the telephone handset control units 48 provided in each are called telephone handset control units 48-1 and 48-2, and the telephone handsets 20 are called telephone handsets 20-1 and 20-2.

As shown in Figure 7, a call is made from the telephone handset control unit 48-1 of the telephone repeater 18-1, and a call connection is established between the telephone base unit 28 and the telephone handset 20-1 through call control between the telephone base unit control unit 46 of the receiver 10. The call control in steps S51 to S59 in this case is the same as steps S21 to S29 in Figure 5, so a description thereof will be omitted.

Next, when the telephone handset control unit 48-2 of another telephone repeater 18-2 determines in step S60 that the telephone handset 20-2 has been off-hook, a line connection sound is output from the telephone handset 20-2, and then in step S61, the telephone base unit 28 transmits a call command signal including its own address via the transmission lines 12a and 12b to the receiver 10 currently in a call.

When the telephone base unit control unit 46 of the receiver 10 receives the call command signal transmitted from the telephone repeater 18-2, in step S62 it displays a call to the telephone handset 20-2 on the display 30 and also outputs a predetermined warning sound from the speaker of the alarm unit 33.

As a result, when the person on the call realizes that there is a call from another telephone handset 20-2 and performs a selection operation, the telephone base unit control unit 46 recognizes the selection operation for the other telephone handset 20-2 in step S63 and proceeds to step S64, sending an incoming call response command signal specifying the address of the telephone repeater 18-2 to the transmission lines 12a and 12b. This is received by the telephone repeater 18-2, and the telephone handset control unit 48-2 connects the telephone handset 20-2 to the telephone lines 16a and 16b in step S65.

In addition, in step S66, the telephone base unit control unit 46 transmits a hold command signal specifying the address of the telephone repeater 18-1 of the telephone handset 20-1, which had been in communication up until then, to the transmission lines 12a and 12b. This signal is received by the telephone repeater 18-1, and in step S67, the telephone handset control unit 48-1 disconnects the call by disconnecting the telephone handset 20-1 from the telephone lines 16a and 16b, and also causes the telephone handset 20-1 to output a specified hold tone.

After that, when the call between the base unit 28 and the handset 20-2 ends and the handset control unit 48-2 determines that the call is on-hook in step S68, the process proceeds to step S69, where a call end command signal including the handset's own address is sent to the transmission lines 12a and 12b.

When the telephone base unit control unit 46 determines that it has received a call end command signal from the telephone repeater 18-2, it sends a hold release command signal specifying the address of the telephone repeater 18-1 that is on hold to the transmission lines 12a and 12b in step S70. When the telephone handset control unit 48-1 receives a hold release command signal specifying its own address, it stops the output of the hold tone from the telephone handset 20-1 in step S71, reconnects the telephone handset 20-1 to the telephone lines 16a and 16b, and resumes the call with the telephone base unit 28.

(3-way call)
Figure 8 is a time chart showing the call control of a three-way call using a telephone base unit and two telephone handsets. As in Figure 7, the two telephone repeaters 18, telephone handsets 20, and telephone handset control unit 48 that make up the three-way call are telephone repeaters 18-1 and 18-2, telephone handsets 20-1 and 20-2, and telephone handset control units 48-1 and 48-2, respectively.

In the three-way call shown in Figure 8, the control of steps S81 to S92 is the same as steps S51 to S62 shown in Figure 7, so a description of this will be omitted.

In the three-way call shown in Figure 8, when a call is connected between the base station 28 and the handset 20-1, if a call command signal is sent from the telephone repeater 18-2 of another handset 20-2 and a call to the handset 20-2 is displayed on the display 30 in step S92, a three-way call selection button will appear on the display screen, allowing the user to select the three-way call.

Therefore, when the telephone base unit control unit 46 recognizes the selection operation for three-way calling in step S93, the process proceeds to step S94, where an incoming call command signal specifying the address of the telephone repeater 18-2 that sent the outgoing call command signal is sent to the transmission lines 12a and 12b. Upon receiving this, the telephone handset control unit 48-2 connects the telephone handset 20-2 to the telephone lines 16a and 16b in step S95.

Next, in step S96, the telephone base unit control unit 46 sequentially transmits three-way call command signals specifying the addresses of the telephone repeaters 18-1 and 18-2 to the transmission lines 16a and 16b. Upon receiving this, the telephone handset control units 48-1 and 48-2 output a predetermined message from the telephone handsets 20-1 and 20-2 in steps S97 and S98 notifying the start of the three-way call. As a result, the three-way call shown in step S99 of the telephone base unit control unit 46 and steps S100 and S101 of the telephone handset control units 48-1 and 48-2 is established by connecting the telephone base unit 28 and the telephone handsets 20-1 and 20-2 to the telephone lines 16a and 16b.

Here, four-way or five-way calls can be realized by connecting multiple telephone handsets 20 in addition to the telephone base unit 28 to the telephone lines 16a and 16b. However, as the number of telephones connected to the telephone lines 16a and 16b increases, the level of the audio signals transmitted by the telephone lines 16a and 16b decreases, deteriorating the quality of the call. Therefore, three-way calls are optimal, in which three telephones, each connected to two telephone handsets in addition to the telephone base unit 28, which causes less degradation in audio level, are connected to the telephone lines 16a and 16b.

(Call control performed by connecting a maintenance telephone handset to a telephone jack)
FIG. 9 is a time chart showing call control performed when an emergency telephone handset is connected to a telephone jack.

As shown in Figure 9, when a person carrying the maintenance telephone handset 40 inserts the plug 42 of the maintenance telephone handset 40 into the telephone jack 38 of the transmitter 36 in step S111 to contact the receiver 10, the maintenance telephone handset 40 is connected to the telephone lines 16a and 16b, line current flows, and the call detection circuit unit 35 of the receiver 10 detects a drop in line voltage in step S112 and outputs a call detection signal to the telephone base unit control unit 46.

The telephone base unit control unit 46, which receives the call detection signal from the call detection circuit unit 35, instructs the alarm unit 33 to output a call tone from the speaker in step S113, thereby making a call, and then proceeds to step S114, where the display 30 displays a message indicating that the maintenance telephone handset 40 is being called.

When the person in charge picks up the telephone base unit 28 installed on the receiver 10 in response to the ring tone in step S113, the telephone base unit control unit 46 determines in step S115 that the telephone base unit 28 is off-hook, and in step S116 instructs the connection switching unit 62 to turn on the switch circuit unit 66, thereby connecting the telephone base unit 28 to the telephone lines 16a and 16b for communication, and a communication connection is established with the maintenance telephone handset 40.

When the call ends, the telephone base unit 28 is returned, and the telephone base unit control unit 46 determines in step S117 that the telephone base unit 28 is on-hook, and in step S118 performs a call disconnection to disconnect the telephone from the telephone lines 16a and 16b, thereby terminating the call connection.

Furthermore, when the call ends, the maintenance telephone handset 40 is removed from the telephone jack 38 in step S119, and the connection to the telephone lines 16a and 16b is released. As a result, in step S120, the line voltage is restored in the call detection circuit unit 35, and the output of the notification detection signal is stopped.

[Fire alarm system with emergency telephone equipment and maintenance telephone equipment]
(Facility overview)
FIG. 10 is an explanatory diagram showing an embodiment of a fire alarm system having a call control function for emergency telephone equipment linked to emergency broadcast equipment and maintenance telephone equipment used for maintenance and inspection.

As shown in Figure 10, transmission lines 12a and 12b for the fire alarm system, emergency telephone lines 16c and 16d for the emergency telephone system, and maintenance telephone lines 84a and 84b for the maintenance telephone system are drawn from the receiver 10 to the restricted area.

Transmission lines 12a and 12b are connected to multiple fire detectors 14 with transmission functions and unique addresses, repeaters 15, and addressable transmitters 37. Furthermore, transmission lines 12a and 12b and emergency telephone lines 16c and 16d are connected to multiple telephone repeaters 18 equipped with emergency telephone handsets 20a. Each telephone repeater 18 is assigned a unique address and has transmission and call control functions.

In addition, a transmitter 36 is connected to the repeater 15 of the transmission lines 12a and 12b. The transmitter 36 is equipped with a transmitter button 36a, and when the transmitter button 36a is pressed to turn it on in the event of a fire, a transmission signal is output to the repeater 15. A fire notification signal is then sent from the repeater 15 to the receiver 10 via the transmission lines 12a and 12b, and a fire alarm is output.

The transmitter 36 is provided with a telephone jack 38, which is connected to maintenance telephone lines 84a and 84b. When the plug 42 of the maintenance telephone handset 40a carried by the person in charge is inserted into the telephone jack 38, the maintenance telephone handset 40a is connected to the maintenance telephone lines 84a and 84b, and a call connection is established with the telephone base unit 28 provided in the receiver 10, allowing the call to be made.

Like transmitter 36, addressable transmitter 37 is also provided with transmitter button 37a. When transmitter button 37a is pressed to turn it on in the event of a fire, a fire notification signal is sent from transmitter 37b to receiver 10 via transmission lines 12a and 12b, and a fire alarm is output.

Like transmitter 36, addressable transmitter 37 is equipped with a telephone jack 38, which is connected to maintenance telephone lines 84a and 84b. When the plug 42 of the maintenance telephone handset 40a carried by the person in charge is inserted into telephone jack 38, the maintenance telephone handset 40a is connected to the maintenance telephone lines 84a and 84b, and a call connection is established with the telephone base unit 28 installed in the receiver 10, allowing calls to be made.

The receiver 10 is provided with a telephone base unit 28 corresponding to the emergency telephone handset 20a and maintenance telephone handset 40a.

In addition to the fire alarm system, this embodiment is also equipped with emergency broadcasting equipment. Broadcast lines 92 are drawn from an emergency broadcast panel 90 installed in the same building as the receiver 10, such as the manager's room, to the restricted area, for example, by floor, and speakers 94 for broadcasting are connected to the broadcasting lines 92.

(Receiver functional configuration)
The receiver 10 includes a receiving control unit 22, a transmission unit 24, an emergency telephone base unit circuit unit 26a, a maintenance telephone base unit circuit unit 26b, a telephone base unit 28, a display 30 with a touch panel, a display unit 31, an operation unit 32, an alarm unit 33 with a speaker, a notification unit 34, a call detection circuit unit 35, and a switching unit 82.

The reception control unit 22 of the receiver 10 is provided with the functions of the telephone base unit control unit 46, which are realized by the CPU executing a program. The fire monitoring control unit 44 is the same as in the embodiment shown in Figure 1, so its description will be omitted.

(Telephone base unit control unit)
The telephone base unit control unit 46 performs call control for incoming calls to the emergency telephone handset 20a, call control for incoming calls to the maintenance telephone handset 40a, and call control when incoming calls to the emergency telephone handset 20a and the maintenance telephone handset 40a overlap.

The telephone repeater 18 is the same as that shown in Figure 2, and the call detection circuit unit 35 is the same as that shown in Figure 3. The emergency telephone base unit circuit unit 26a and the maintenance telephone base unit circuit unit 26b are basically the same as the telephone base unit circuit unit 26 in Figure 3, but differ in that a switching unit 82 is provided between the base telephone 28, which switches the base telephone 28 to the emergency telephone base unit circuit 26a when an emergency call is received, and switches the base telephone 28 to the maintenance telephone base unit circuit unit 26b when a maintenance call is received.

Call Control
The telephone base unit control unit 46 displays the operations required for call control with the telephone base unit 28 on the display 30 based on a call command signal including the caller address from the emergency telephone handset 20a via the telephone repeater 18 and repeater 15, and/or based on a call detection signal from the call detection circuit unit 35, and performs the following call control based on screen operations, etc.

(Maintenance call incoming)
During regular inspections, etc., when the plug 42 of the maintenance telephone handset 40a carried by an inspection personnel is inserted into the telephone jack 38 of the transmitter 36 or addressable transmitter 37 to connect to the maintenance telephone lines 84a, 84b, the call detection circuit unit 35 of the receiver 10 detects the line current flowing through the connection of the maintenance telephone handset 40a and outputs a call detection signal to the telephone base unit control unit 46.

When the call detection signal is input from the call detection circuit unit 35, the telephone base unit control unit 46 displays an incoming maintenance call on the display 30, outputs a specified maintenance call ringtone (maintenance call ringtone) from the speaker of the alarm unit 33, and switches the telephone base unit 28 to the maintenance telephone base unit circuit unit 26b via the switching unit 82.

When a disaster prevention manager or other person on the receiver 10 side who has received such an incoming maintenance call picks up the telephone base unit 28, the telephone base unit 28 detects an off-hook state and connects to the maintenance telephone handset 40a that made the call via the maintenance telephone base unit circuit section 26b and the maintenance telephone lines 84a and 84b, allowing the necessary call to be made.

(Emergency call incoming)
If a watchman or the like discovers a fire while on patrol, he or she picks up the nearby emergency telephone handset 20a, which turns on the hook switch and sends a call command signal including the caller's address to the receiver 10 via the telephone repeater 18 and the repeater 15. Upon receiving the call command signal from the emergency telephone handset 20a, the telephone base unit control unit 46 of the receiver 10 displays on the display 30 the incoming emergency call along with the caller's location based on the caller's address, outputs a predetermined emergency call ringtone (emergency call tone) from the speaker of the alarm unit 33, and switches the telephone base unit 28 to the emergency telephone base unit circuit unit 26a by the switching unit 82.

When a disaster prevention manager or other person on the receiver 10 side notices an incoming emergency call and picks up the base telephone unit 28, the base telephone unit 28 detects an off-hook state and connects to the handset 20a that made the call via the emergency telephone lines 16c and 16d, allowing the necessary call to be made.

Furthermore, when the telephone base unit control unit 46 of the receiver 10 receives a call command signal from the emergency telephone handset 20a via the telephone repeater 18 and repeater 15, it instructs the notification unit 34 to output a fire notification signal including the fire area based on the caller address to the emergency broadcast panel 90 within a predetermined time, for example, within 10 seconds.

When the emergency broadcast panel 90 receives the fire transmission signal from the receiver 10, it designates the fire floor and the floor directly above it as the fire area, and broadcasts a fire announcement. For example, this fire announcement may say, "Fire! Fire! A fire has broken out in the XX area. Please remain calm and evacuate." Furthermore, once a predetermined time has passed since the start of the emergency announcement, the emergency broadcast panel 90 broadcasts an emergency announcement to the entire building simultaneously in all broadcast areas.

(Duplicate emergency calls)
Furthermore, when calls from multiple emergency telephone handsets 20a overlap, the telephone base unit control unit 46 of the receiver 10 displays the multiple call sources on the display 30 and controls the call connection to the emergency telephone handset 20a of the call source selected by operating the screen. At this time, the telephone base unit control unit 46 controls the output of a hold tone from the emergency telephone handsets that were not selected.

(Duplicate calls from emergency and maintenance calls)
Furthermore, when an emergency call and a maintenance call are received at the same time, the base unit control unit 46 of the receiver 10 displays the emergency call and the maintenance call on the display 30, and controls the call connection to the emergency call or the maintenance call selected by operating the screen. At this time, the base unit control unit 46 controls the caller not to select a hold tone. Priorities may be set in advance for the emergency call and the maintenance call, and the caller with the highest priority may be selected for the call connection.

(Alternative display of emergency and maintenance telephone numbers)
In addition, an incoming call to the emergency telephone handset 20a may be displayed on the display 30, and an incoming call to the maintenance telephone handset 40a may be displayed by a maintenance telephone light located in the panel. Since the emergency telephone handset 20a transmits an emergency call signal including a unique caller address, it is possible to identify the installation location, so it is preferable to indicate the caller on the display 30.

(Communication of connection location identification information when connecting a maintenance telephone handset)
When the maintenance telephone handset 40a is connected to the transmitter 36 or the addressable transmitter 37, the transmitter 36 or the addressable transmitter 37 detects the plug connection and transmits address information on the transmission circuit to the receiver 10, and the receiver 10 may display information specifying the transmitter 36 or the addressable transmitter 37 to which the maintenance telephone handset 40a is connected from the information. By making it possible to display whether the call originated from the emergency telephone handset 20a or the maintenance telephone handset 40a, it becomes possible to help determine which call to prioritize.

[Modifications of the present invention]
(telephone jack)
In the above embodiment, a telephone jack is provided on the transmitter, but a telephone jack may be provided on an appropriate terminal device as needed. Furthermore, the maintenance telephone equipment is not limited to a portable type, and may be a maintenance telephone handset that is fixedly installed in the security zone and plugged into a telephone jack for use.

The telephone jack may also be provided on the receiver 10. For example, the positive and negative sides of the telephone jack are connected via capacitors between the telephone lines 16a and 16b drawn out from the call detection circuit unit 35 shown in Figure 3 to the terminal side. In this case, a call connection can be established between the maintenance telephone handsets by plugging them into the receiver's telephone jack and the transmitter's telephone jack.

(Maintenance handset priority and handset hold tone)
In the above embodiment, when the telephone base unit control unit 46 detects a connection of the maintenance telephone handset 40 to the telephone jack 38 during a call connection between the telephone base unit 28 and one of the emergency telephone handsets 20, it notifies the caller of the maintenance telephone handset 40a, switches the call connection to the maintenance telephone handset 40, and sends a hold command signal specifying the address of the telephone relay unit 18 of the emergency telephone handset 20 that is currently in use, thereby disconnecting the emergency telephone handset 20 from the telephone lines 16a, 16b and outputting a predetermined hold tone.

As a result, when the maintenance telephone handset 40 is connected to the telephone jack 38 while a call is in progress between the telephone base unit 28 and the emergency telephone handset 20, the previous call connection between the telephone base unit 28 and the emergency telephone handset 20 is put on hold, and the call with the maintenance telephone handset 40 takes priority.

Also, when the call between the telephone base unit 28 and the maintenance telephone handset 40 ends, the telephone base unit control unit 46 may send a hold release command signal specifying the address of the telephone relay unit 18 of the emergency telephone handset 20 on hold, connecting the emergency telephone handset 20 to the telephone lines 16a and 16b and restoring the call between the telephone base unit 28 and the emergency telephone handset 20.

(Calls between telephone handsets)
The above embodiment takes as an example call control between the receiver's telephone base unit and a telephone handset installed in a security zone, but is not limited to this. By providing an operation display unit that inputs a telephone number into the telephone repeater to make a call, it is also possible to make calls between telephone handsets by calling from one telephone handset to another telephone handset.

(Hands-free calling function)
The above embodiment takes as an example a call between a telephone base unit and a telephone handset, but is not limited to this. In addition to the telephone base unit of the receiver and the telephone handset of the telephone repeater, a microphone and speaker may be installed on a panel surface near the telephone, and a hands-free call function may be provided in which the telephone can be switched to a microphone and speaker by operating a specified switch, allowing calls to be made without using the telephone.

(P-type receiver)
The above embodiment takes as an example a fire alarm system in which an R-type fire detector is connected via a transmission line from an R-type receiver, but similar communication control can also be achieved in a fire alarm system in which an addressable fire detector with a transmission function is connected and an address is set on the detector line drawn from a P-type receiver, by sending and receiving various command signals using the detector line.

(others)
Furthermore, the present invention includes appropriate modifications that do not impair the objects and advantages thereof, and is not limited to the numerical values shown in the above embodiments.

10: Receiver 12a, 12b: Transmission line 14: Fire detector 15: Repeater 16a, 16b: Telephone line 16c, 16d: Emergency telephone line 18: Telephone repeater 20: Telephone handset 20a: Emergency telephone handset 22: Reception control section 24, 50: Transmission section 26: Telephone base unit circuit section 26a: Emergency telephone base unit circuit section 26b: Maintenance telephone base unit circuit section 28: Telephone base unit 30: Display 35: Call detection circuit section 36: Transmitter 37: Addressable transmitter 38: Telephone Jack 40: Maintenance telephone handset 40a: Maintenance telephone handset 44: Fire monitoring control unit 46: Telephone base unit control unit 45, 72: Receiver 47, 74: Transmitter 48: Telephone handset control unit 52, 62: Connection switching unit 54, 64: Control sound generating unit 56, 66: Switch circuit unit 58, 68: Transformer 60, 70: Hook switch 61, 94: Speaker 76, 78, 80: Resistor 82: Switching unit 84a, 84b: Maintenance telephone line 90: Emergency broadcast panel 92: Broadcast line

Claims (3)

a transmission line connecting a terminal device including a telephone repeater located in the security zone with a receiver;
a first telephone line connecting the telephone repeater and the receiver;
a second telephone line connecting the receiver to a telephone jack located in the security zone;
A fire alarm system equipped with
the receiver stores address information that can identify the telephone repeater, and is capable of making a call connection with a first telephone handset connected to the first telephone line via the telephone repeater and a second telephone handset connected to the second telephone line via the telephone jack;
The receiver and the first handset are connected for communication by controlling transmission and reception of a predetermined call control signal via the transmission line between the receiver and the telephone repeater to which the first handset is connected,
The receiver and the second handset are connected for communication by connecting the second handset to the telephone jack,
When an incoming call is received from the first handset, a display indicating that an incoming call has been received is displayed so as to identify the first handset that is the source of the incoming call, based on the address information of the telephone repeater to which the first handset that is the source of the incoming call is connected;
A fire alarm system characterized in that, when an incoming call is received from the second handset, an announcement is made indicating that an incoming call has been received from the second handset.
a transmission line connecting a terminal device including a telephone repeater located in the security zone with a receiver;
a first telephone line connecting the telephone repeater and the receiver;
a second telephone line connecting a second telephone handset located in the security zone to the receiver;
A fire alarm system equipped with
the receiver stores address information that can identify the telephone repeater, and is capable of making a call connection with a first telephone handset connected to the first telephone line and a second telephone handset connected to the second telephone line via the telephone repeater;
the receiver and the first handset are connected to be able to make a call by controlling transmission and reception of a predetermined call control signal via the transmission line between the receiver and the telephone repeater to which the first handset is connected,
the receiver and the second handset are connected to be able to make a call when the receiver detects an electrical change in the second telephone line in response to a call start request operation using the second handset,
When an incoming call is received from the first handset, a display indicating that an incoming call has been received is displayed so as to identify the first handset that is the source of the incoming call, based on the address information of the telephone repeater to which the first handset that is the source of the incoming call is connected;
A fire alarm system characterized in that, when an incoming call is received from the second handset, an announcement is made indicating that an incoming call has been received from the second handset.
The fire alarm system according to claim 1 or 2,
A fire alarm system characterized in that the notification indicating that an incoming call has been received from the second telephone handset is made by outputting a second telephone handset ringtone indicating that an incoming call has been received from the second telephone handset.