JPH06103519B2 - Fire detection terminal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a fire detection terminal, and is used for an automatic fire alarm system using a time division multiplex transmission technique.

[Prior Art] FIG. 2 is a schematic configuration diagram of an automatic fire alarm system using a time division multiplex transmission system. In this system, N receivers T ₁ , T ₂ , ..., T _N for fire detection are monitored by one receiver (or relay) R. Each of the terminals T _{1 to} T _N is a transmission line l
And the base B ₁ .about.B _N which is connected to the receiver R through, made from the head H ₁ to H _N which is removably attached to the base B ₁ ~B _N. The heads H _{1 to} H _N have built-in fire detectors that generate analog fire detection signals. Bases B _{1 to} B _N are heads H ₁
The analog fire detection signal obtained from ~ H _N is converted into a digital signal, and this digital signal is returned to the receiver R.

Fire detectors built into the heads H _{1 to} H _N include smoke concentration sensors that generate analog signals according to smoke concentration, room temperature sensors that generate analog signals according to room temperature, or flames. There are several types such as infrared detectors that generate analog signals according to the detected amount of infrared rays with a wavelength of 4.3 μm. Therefore, in the receiver R, at the time of initial polling in which each of the terminals T _{1 to} T _N is first polled, each of the terminals T _{1 to} T _{N is}
A signal indicating the type of fire detector included in is sent back to the receiver R, and a table indicating the correspondence between the addresses of the terminals T _{1 to} T _N and the type of fire detector is created. Then, at the time of subsequent polling, it is discriminated based on the above table whether the signals returned from the terminals T _{1 to} T _N are smoke density signals, room temperature detection signals, or infrared detection signals. .

Signals indicating the type of such a fire detector are sent to the heads H _{1 to} H _N.
To provide the base B ₁ .about.B _N from the head H ₁ to H _N to the other analog signal terminals, and a type terminals. Also, since the heads H _{1 to} H _N receive power from the bases B _{1 to} B _N ,
It has a power supply terminal and a common terminal (ground terminal).
Therefore, the heads H _{1 to} H _N and the bases B _{1 to} B _N are connected by four terminals.

[Problems to be Solved by the Invention] In an automatic fire alarm system, it is necessary to regularly inspect whether or not each fire sensor can be normally alarmed. However, in a system that mixes various types of fire detectors as described above, it is necessary to generate smoke near the fire detector, raise the room temperature, or generate infrared rays caused by flames. Moreover, since the fire detectors are distributed over a wide range, it is necessary to generate many kinds of pseudo fires at different places, which makes it difficult to perform regular inspections. Therefore, it is possible to remotely transmit the alarm test test of many types of fire detectors by transmitting the alarm test signal from the receiver R to each of the terminals T _{1 to} T _N without actually causing a pseudo fire. Conceivable. However, in the above system, each terminal
Since T ₁ through T _N are separated into the base B ₁ .about.B _N and the head H ₁ to H _N, in order to transmit the alarm test signal from the base B ₁ .about.B _N to the head H ₁ to H _N, There is a problem that one additional connection terminal must be added.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a head having a built-in fire detector that outputs an analog signal necessary for fire detection, and digitize and transmit the analog signal. In the fire detection terminal including the base, the number of connecting terminals between the head and the base is reduced by sharing the type terminal and the alarm test terminal.

[Means for Solving the Problem] In order to solve the above-mentioned problems, the fire detection terminal device according to the present invention, as shown in FIG. 1, outputs an analog signal necessary for fire detection. Built-in detector 1 and fire test unit 2 that forcibly sets fire detector 1 to the alarm state, and outputs power supply terminal P1 for receiving power supply and analog signal from fire detector 1. The analog signal terminal P2 for operating the fire detector 1, the type terminal P3 for outputting a type signal indicating the type of the fire detector 1, and the common terminal P4 shared by the terminals P1 to T3 are provided. Trial test section 2
Head H connected to the control input of the first resistor R1 for indicating the type of the fire detector 1 between the type terminal P3 and the common terminal P4, and the head H is detachably connected. , A base B that receives an address signal and a control signal via an external transmission line 1 and sends back a reply signal. The base B is an address setting unit 3 that sets a unique address, and an external transmission line. When the address signal received via l matches the set address of the address setting unit 3,
The transmission controller 4 that selectively executes the fire monitoring operation, the type reply operation, and the alarm test operation according to the control signal corresponding to the address signal, and the first resistor R1 and the reference voltage V _ref are divided. The second resistor R2 that creates the type signal and the analog signal obtained at the analog signal terminal P2 during the fire monitoring operation and the alarm test operation is digitized to be the reply signal of the transmission control unit 4, and during the type reply operation, the type A / D converter 5 that digitizes the type signal obtained at the terminal P3 and uses it as the return signal of the transmission control unit 4, and terminal switching that gives a notification test signal from the transmission control unit 4 to the type terminal P3 during the alarm test operation. And a section 6.

[Operation] In the present invention, as described above, the transmission for selectively executing the fire monitoring operation, the type reply operation, and the alarm test operation according to the control signal externally received via the transmission line l. The control unit 4 and the type control terminal P3 from the transmission control unit 4 during the alarm test operation.
Is provided on the base B, and the head H is forced to set the fire detector 1 to the alarming state according to the alarming test signal obtained from the type terminal P3. Since the test unit 2 is provided, the connection terminals between the head H and the base B are the power supply terminal P1, the analog signal terminal P2, and the type terminal.
With the four terminals of P3 and common terminal P4 remaining, it is possible to carry out the alarm test by remote control.

[Embodiment] FIG. 1 is a block diagram of a fire detection terminal T according to an embodiment of the present invention. The fire detection terminal T includes a head H for fire detection and a base B for signal transmission. The head H has a built-in analog fire detector 1. The fire detector 1 includes, for example, a smoke concentration sensor that generates an analog signal according to smoke concentration, a room temperature sensor that generates an analog signal according to room temperature, or infrared rays with a wavelength of 4.3 μm included in a flame. There are a plurality of types such as an infrared sensor that generates an analog signal according to the detection amount of. Therefore,
The head H has a first resistor R1 incorporated therein for indicating the type of the fire detector 1. The resistance value of the resistor R1 is set to a different value depending on the type of the fire detector 1.
The alarm test unit 2 forcibly sets the fire detector 1 to the alarm state during the alarm test operation described below. The warning state of the fire detector 1 is, for example, a state in which a smoke concentration detection signal having a certain concentration or more, a room temperature detection signal having a certain temperature or more, and an infrared ray detection signal having a certain amount or more are output as analog signals. The fire detector 1 and the alarm test unit 2 are operated by being supplied with power by the power supply voltage supplied between the power supply terminal P1 and the common terminal P4. The analog signal obtained from the fire detector 1 is given to the base B via the analog signal terminal P2. Also, type pin P3
Is also used as the alarm test signal terminal, and at the time of the type reply operation described later, a voltage corresponding to the value of the resistor R1 is generated at the type terminal P3 as an analog signal, and during the alarm test operation described later, the resistor R1 Is used as an input resistance to input the alarm test signal to the control input of the alarm test section 2.

The base B includes a transmission control unit 4 connected to an external transmission line 1. The transmission line 1 is 2 such as a coaxial cable.
It is composed of a wire type cable, and as shown in FIG. 2, a plurality of terminals T _{1 to} T _N and one receiver R are connected in parallel between the lines. From the receiver R, a start signal indicating the start of signal transmission, an address signal for designating a terminal device to communicate with, a control signal for controlling the operation of the terminal device, and a reply signal from the terminal device are received. A time-division multiplex transmission signal including at least a reply time zone for sending the signal and an end signal indicating the end of signal transmission is sent to the transmission line l. The address signal and the control signal are, for example, a plurality of bits (for example, 8 bits) serial signals meaning that the long voltage pulse is “1” and the short voltage pulse is “0”. In the reply time zone, for example, the receiver R
By applying a voltage between the transmission lines 1 on the side of and a short circuit between the transmission lines 1 on the side of the terminal via a resistor, for example, a long current pulse is "1" and a short current pulse is " A multi-bit (for example, 8 bits) serial signal meaning "0" is returned to the receiver R. The address signal and the control signal are sent from the receiver R as a low impedance voltage signal,
In the base B ₁ .about.B _N of each terminal device T ₁ through T _N, connect the rectifier and a smoothing capacitor between the line of the transmission line l, to obtain operating power. The reference voltage V _ref is generated from this operating power supply
Supplying power to P1.

The address signal included in the time division multiplex transmission signal transmitted from the receiver R has changed so as to cyclically poll each of the terminal units T _{1 to} T _N, and only one terminal unit whose address signal matches Performs a control operation and a reply operation according to the control signal. In order to allocate this address signal, the base B has an address setting unit 3. The address setting unit 3 is composed of a DIP switch, an E ² PROM or the like, and sets a unique address signal so that each of the terminals T _{1 to} T _N does not overlap. When the start signal is received from the transmission line 1, the transmission control unit 4 receives the address signal that follows the start signal and collates it with its own address signal set in the address setting unit 3. If the address signals do not match, it waits for the next start signal to be received. If the address signals match, the control signal that follows is received, and the fire monitoring operation, the type reply operation, and the alarm test operation are selectively executed according to the control signal. Hereinafter, each operation will be described.

(I) Type reply operation When the receiver R performs the first polling after system construction,
A control signal designating the type reply operation is given to each terminal T _{1 to} T _N. In this case, the terminal T polled from the receiver R divides the reference voltage V _ref by the resistor R2 in the base B and the resistor R1 in the head H to obtain the voltage of the type terminal P3. , Converted to digital signal by A / D converter 5,
Reply to receiver R. Thus, memory address of the receiver R in each terminal unit T ₁ through T _N, the correspondence between the type of the terminal unit T ₁ through T _N fire detector 1 built into a table.

(Ii) Fire monitoring operation At the second and subsequent polling, the receiver R gives a control signal designating the fire monitoring operation to each of the terminals T _{1 to TN} . In this case, the terminal device T polled by the receiver R converts the analog signal obtained from the fire detector 1 through the analog signal terminal P2 into a digital signal by the A / D conversion unit 5, and then the receiver device R receives the analog signal. Reply. As a result, in the receiver R,
The analog signals required to fire from each terminal device T ₁ through T _N can be received digitized, by referring to the table created at the time of initial poll, the received signal is a signal indicating the smoke density Whether the signal indicates the room temperature or the infrared ray detection amount.

(Iii) Notification Test Operation Next, at the time of regular inspection, the receiver R gives a control signal designating the report test operation to each of the terminals T _{1 to} T _N. In this case, the terminal device T polled by the receiver R has the transmission control unit 4
The terminal switching unit 6 is switched under the control of 1 to input the alarm control signal from the transmission control unit 4 to the alarm test unit 2 via the terminal switch unit 6 and the type terminal P3. The content of the alarm control signal is not particularly limited, but it is sufficient if the signal is different from the predetermined voltage signal obtained at the type terminal P3 during the fire monitoring operation or the type reply operation. With this alarm control signal, the alarm test unit 2 operates and the fire detector 1 is forcibly set to the alarm state. That is, the analog signal output from the fire detector 1 has a voltage level when a fire occurs. This analog signal is input to the A / D conversion unit 5 via the analog signal terminal P2, converted into a digital signal, and returned from the transmission control unit 4 to the receiver R. As a result, the receiver R can remotely perform the alarm test of the fire detector 1 incorporated in each of the terminals T _{1 to} T _N.

[Effects of the Invention] In the present invention, as described above, a head having a built-in fire detector that outputs an analog signal necessary for fire detection,
In a fire detection terminal consisting of a base that digitizes and transmits the above analog signal, the head has a built-in alarm test unit that forcibly sets the fire sensor to the alarm state, and receives it from the outside via a transmission line. Based on the transmission control unit that selectively executes the fire monitoring operation, the type reply operation, and the alarm test operation according to the generated control signal, and the terminal switching unit that switches the function of the type terminal under the control of the transmission control unit. Since it is built in, the type terminal for giving the type signal from the head to the base during the type reply operation is used as the alarm test signal terminal for giving the alarm test signal from the base to the head during the alarm test operation. This has the effect of reducing the number of connecting terminals between the head and the base.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram of a conventional automatic fire alarm system. 1 is a fire detector, 2 is an alarm test unit, 3 is an address setting unit, 4 is a transmission control unit, 5 is an A / D conversion unit, 6 is a terminal switching unit, P1 is a power supply terminal, P2 is an analog signal terminal, P3 is a type terminal, P4 is a common terminal, B is a base, H is a head, and 1 is a transmission line.

Claims (1)

[Claims] 1. A power supply terminal for receiving a power supply, which includes a fire detector that outputs an analog signal necessary for fire detection and a reporting test unit that forcibly sets the fire detector to a reporting state. And an analog signal terminal for outputting an analog signal from the fire detector, a type terminal for outputting a type signal indicating the type of the fire detector, and a common terminal shared for each terminal, The type terminal is connected to the control input of the alarm test unit, and the head to which the first resistor for indicating the type of the fire detector is connected between the type terminal and the common terminal is detachably connected to the head. It is composed of a base that receives an address signal and a control signal via an external transmission line and sends back a reply signal.The base is an address setting unit that sets a unique address and an external transmission line. Received When the reply signal matches the set address of the address setting unit, the transmission control unit that selectively executes the fire monitoring operation, the type reply operation, and the alarm test operation according to the control signal corresponding to the address signal, A second resistor that divides the reference voltage together with the 1st resistor to create a type signal, and an analog signal obtained at the analog signal terminal during the fire monitoring operation and the alarm test operation is digitized and returned by the transmission control unit. Signal, the A / D converter that digitizes the type signal obtained at the type terminal during the type reply operation and becomes the return signal of the transmission control unit, and the alarm test signal from the transmission control unit to the type terminal during the alarm test operation. A fire detection terminal, comprising: a terminal switching unit for giving.