JPH0229501Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention utilizes a telephone line installed in hotels, etc., which centrally monitors fire detectors installed in each room on the exchange side. Regarding fire alarms.

Conventionally, fire alarm systems for monitoring fires in each room of a hotel or the like require a dedicated signal line to be installed from a fire receiver installed in a central monitoring room to the fire detectors in each room.

By the way, in buildings such as hotels, dedicated private telephone equipment is generally installed to allow communication between each room and the front desk. If fire detectors could be centrally monitored using these telephone lines, it would be possible to eliminate the need for a dedicated signal line for fire alarms.

The present invention was developed with a focus on this point.
The fire detector is connected via an adapter near the handset of the local telephone installed in each room of a hotel, etc., and power is supplied to the fire detector by the direct current voltage of the telephone line, and when a fire is detected, all lines are connected. An AC signal with a common specific frequency is oscillated and superimposed on the telephone line, and a fire receiver installed near the exchange identifies the room where the fire detector has activated based on the line that receives the AC signal with the specific frequency. The purpose of the present invention is to provide a fire alarm system that uses a telephone in the premises, which allows easy and simple installation of the fire alarm system, and does not require a dedicated line, thereby significantly reducing equipment costs. do.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 1 is an explanatory diagram showing the overall configuration of the present invention.

First, to explain the configuration, numeral 10 is a switchboard for a private telephone, and telephone handsets 14a and 1 are installed in each room.
A pair of telephone lines 12 for each of 4b,...
a to 12n are connected. Telephone handset 14a, 1
4b, . . . near the adapters 16a, 16b, .
... are provided, and these adapters 16a, 16b, ...
Fire detectors 18a, 18b, ... are connected through ..., and outdoor indicator lights 20a, 20b, ..., which light up when the fire detector is activated, are connected to each of the adapters 16a, 16b, ... has been done.

On the other hand, telephone lines 12a~ near the exchange 10 side
12n is provided with adapters 22a to 22n,
The adapters 22a to 22n connect the telephone lines 12a to 1 to the fire receiver 24 installed near the exchange 10.
2n are branch-connected.

FIG. 2 is a circuit block diagram showing an adapter installed near the telephone cordless handset shown in the embodiment of FIG. 1. The adapter 16 connects a pair of telephone lines 12,
12' is connected to the telephone handset 14, and the telephone line 12 on the positive side is connected to the storage battery 26 via the diode D1 and resistor R1.
The storage battery 26 is charged by the DC voltage applied to the terminals 2 and 12'. The positive side of the storage battery 26 supplies power to the fire detector 18 via a recovery switch 32 and a relay 28, and the fire detector 18 is an ionization type that detects fire by supplying power from the storage battery 26 A smoke detector or a photoelectric smoke detector is used.
Relay 28 has relay contacts 28a, 28b, 28c
When the fire detector 18 is activated, the current flowing through the relay coil 28 closes the relay contacts 28a to 28c.

An oscillation circuit 30 is connected to the relay contact 28a side, and the oscillation circuit 30 receives power from the storage battery 26 and generates an alternating current of a predetermined frequency to close the relay contact 28a when the fire detector 18 is activated. The signal is passed through the capacitor C1 to the telephone line 12,1.
Oscillation is output between 2'. The oscillation frequency t of this oscillation circuit 30 is determined as a specific frequency of 4 KHz or more, for example, since the frequency used in the telephone lines 12, 12' is 0.3 to 4 KHz. The oscillation frequency t of this oscillation circuit 30 is determined as a common frequency for adapters provided for all telephone lines.

On the other hand, an outdoor indicator light 20 is connected via the relay contact 28b, and when the relay contact 28b is closed when the fire detector 18 is activated, the outdoor indicator light 20 is turned on to inform the outside of the club room where a fire has occurred. That's what I do. In addition, the relay contact 28e is connected to the relay 2
It is provided for self-holding of 8.

FIG. 3 shows a fire receiver 24 shown in the embodiment shown in FIG.
FIG. 2 is a circuit block diagram showing an embodiment of a receiving circuit provided in the receiving circuit.

That is, the telephone lines 12, 12' branched by the adapter 22 are connected as inputs to the receiver circuit 34, the DC voltage is cut off by the capacitor C2, and only the AC signals superimposed on the telephone lines 12, 12' are taken out. ing. The AC signal taken out via the capacitor C2 is applied to a bandpass filter 36 that passes an AC signal having an oscillation frequency t generated by the oscillation circuit 30 of the adapter 16 shown in FIG. 2, and the output of the bandpass filter 36 is Amplified by an amplifier 38 and a detector 4 using a diode
0, it is converted into a DC voltage, and further stored in a storage circuit 42 consisting of a resistor R2 and a capacitor C3. A switching circuit 44 is provided on the output side of the storage circuit 42, and switches to operate the reception relay 46 when the charging voltage of the capacitor C3 in the storage circuit 42 exceeds a predetermined value. The relay contacts of this reception relay 46 are connected to the telephone lines 12a to 12n connected to the reception circuit 34.
This will turn on the reception display circuit that alerts you to the occurrence of a fire in a room with a telephone handset connected to the end of the telephone. Of course, the receiving circuit 34 shown in FIG. 3 is provided independently for each of the telephone lines 12, 12'. Incidentally, if a scanning circuit that sequentially selects and connects a plurality of telephone lines at regular intervals is used, only one receiving circuit 34 is required.

Next, the operation of the present invention shown in FIGS. 1, 2, and 3 will be explained.

First, in a normal monitoring state where the fire detector is not in operation, the adapter 16 shown in FIG.
The storage battery 26 is constantly charged by the DC voltage applied to the telephone lines 12, 12', and the relay 28
Power is supplied to the fire detector 18 via.
At this time, the DC voltage applied to the telephone lines 12, 12' changes according to the use of the telephone handset, as shown in the time chart of FIG.

That is, as shown in FIG. 4, under normal conditions when the telephone cordless handset is not in use, the telephone line 12
A DC voltage of +48V is applied with the positive side, but when receiving a call from another handset, the ringing signal of the bell will change between zero volts and -48V DC as shown in the period Ta. A pulse signal is given to repeat the cycle, that is, the bell rings for 1 second and pauses for 2 seconds, and when the telephone handset is picked up as shown in the cycle Tb in response to the ringing of the bell, it becomes a talking state with +5V. enter.

In addition, in the case of an outgoing operation using a telephone handset to call another telephone handset, the voltage alternately changes between +48V DC and zero volts according to the dial operation of the telephone handset, as shown in the period Tc. The number of pulse signals corresponding to the number on the dial is transmitted, and when the dialing is finished, the DC voltage becomes +5V during a call, as shown in the period Td, and -5V DC voltage during a call, as shown in the period Te. It brings about a change. The adapter 1 shown in FIG.
Since the storage battery 26 of No. 6 is charged via the diode D1, the storage battery 26 is charged only when a DC voltage is applied with the signal line 12 on the positive side.
is charged, and when a negative voltage is applied with the telephone line 12' side being positive, the diode D1 is reverse biased and the storage battery 26 is prevented from discharging.

Next, if the fire detector 18 detects a fire and is activated, the contacts of the fire detector 18 close, and the storage battery 26 triggers the recovery switch 32 and the relay coil 2.
8. Current flows in the path that becomes the fire detector 18, and therefore the relay 28 is energized and the relay contact 28a
Close each of ~28c. Relay contact 28a
When the oscillation circuit 30 is closed, the power supply voltage of the storage battery 26 is supplied to the oscillation circuit 30, and the oscillation circuit 30 is activated, and the oscillation circuit 30 sends an AC signal of a predetermined frequency t to the telephone lines 12, 12' via the capacitor C1. Also, relay contact 28
By closing the contact point c, the connection terminals of the fire detector 18 are short-circuited, and the relay 28 is self-maintained.Furthermore, by closing the relay contact 28b, the outdoor indicator light 20 is closed.
is lit upon receiving power supply from the storage battery 26.

If the fire detector installed near the telephone handset is activated in this way, an AC signal of a predetermined frequency t is input to the receiving circuit 34 shown in FIG. An AC signal of frequency t is taken out by the pass filter 36, amplified by the amplifier 38, converted to a DC signal by the detector 40, and charged to the capacitor C3 of the storage circuit 42 via the resistor R2.

The switching circuit 44 operates when the terminal voltage of the capacitor C3 in the storage circuit 42 exceeds a predetermined value when the AC signal of the frequency t continues for a certain period of time, and energizes the receiving relay 46 to connect it to the receiving circuit 34. An alarm is displayed for the occurrence of a fire in a room equipped with a telephone handset installed at the terminal of the telephone line 12, 12'.

In this way, when a fire alarm is displayed on the fire receiver 24 installed near the exchanger 10, the supervisor goes to the room where the fire detector is activated and confirms the condition inside the room. If there is a false alarm, the normal monitoring state can be restored by opening the recovery switch 32 of the adapter 16 shown in FIG. 2 and cutting off the power to the relay 28 and oscillation circuit 30.

In the above embodiment, the frequency t of the AC signal sent from the adapter 16 is set to a frequency of 4 KHz or higher, but this is suitable when the exchange 10 can be connected to an outside line; If there is no connection function, a frequency signal within the frequency band of 0.3 to 4 KHz used by telephone lines may be used. In other words, even if the frequency band is within the frequency band used by the telephone line, changes in frequency during normal conversation are due to the frequency output from the oscillation circuit.
Since it does not continue for more than a certain period of time like t, it can be easily identified on the fire receiver side even if it is a frequency within the operating frequency band of 0.3 to 4 KHz.

Further, in the above embodiment, since a telephone line is used, it is not possible to restore the fire detector by cutting off the power at the fire receiver side, and restoration must be performed on-site. Therefore, when a fire is received, the user must go to the scene and check whether there is a fire, which is preferable in terms of disaster prevention management since there is no risk of overlooking the occurrence of an emergency situation.

As explained above, according to the present invention, a fire detector is connected via an adapter near a local telephone installed in each room of a hotel, etc., and In addition to supplying power to the fire detector, when a fire is detected, an AC signal with a specific frequency common to all lines is oscillated and superimposed on the telephone line, and a fire detector installed near the exchange receives the AC signal with a specific frequency. Since the room in which the fire detector was activated can be identified and displayed based on the line in which the fire alarm was activated, the telephone line can also be used as the signal line for the fire alarm, eliminating the need to install a dedicated signal line for the fire alarm. The installation of the alarm system is simple and easy, and since the power supply to the fire detector uses the direct current voltage of the telephone line, there is no need to install a power supply device on the fire receiver side, and there is no need to install a power supply device for each detector. Since the telephone line can be used, the frequency of the AC signal from the adapter of each fire detector can be shared, and therefore the same adapter can be used for each telephone handset, reducing manufacturing costs. At the same time, the installation work becomes easier, and since the use of a telephone line means that if a fire detector is activated, recovery must be done on-site, which is advantageous in terms of disaster prevention management.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the overall configuration of the present invention, Fig. 2 is a block diagram showing an embodiment of the adapter used in the present invention, and Fig. 3 is a block diagram showing an embodiment of the receiving circuit used in the present invention. The circuit block diagram shown, No. 4
The figure is a time chart showing voltage waveforms of the telephone line during reception and transmission. 10...Exchanger, 12, 12, 12a to 12n
...Telephone line, 14,14a-14n...Telephone handset, 16,16a-16n...Adapter, 18,
18a~18n... Fire detector, 20, 20a~
20n...Outdoor indicator light, 22, 22a to 22n...
... adapter, 24 ... fire receiver, 26 ... storage battery, 28 ... relay, 28a-28c ... relay contact, 30 ... oscillation circuit, 32 ... recovery switch, 36 ... bandpass filter, 38 ... Amplifier, 40...Detector, 42...Storage circuit, 44...
...Switching circuit, 46...Reception relay.

Claims (1)

[Scope of Claim for Utility Model Registration] A fire detector is connected via an adapter to the handset of a local telephone installed in each room of a building with multiple rooms, and the adapter detects direct current applied to the telephone line. A storage battery that is constantly charged with voltage and supplies power to the fire detector, and an oscillation that operates with the power supply from the storage battery when the fire detector is activated and sends an alternating current signal of a specific frequency common to all lines to the telephone line. circuit, and a recovery switch that cuts off the power supply to the oscillation circuit and the fire detector, and is connected to each of the telephone lines near the exchange of the premises telephone, and is connected to each of the telephone lines, and is connected to an alternating current of a specific frequency from the oscillation circuit. A fire alarm system using a private telephone, characterized by installing a fire receiver equipped with a reception circuit that identifies and displays a room in which a fire detector has been activated based on the reception line when a signal is received.