JPS58223895A - Fire alarm equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] When the alarm from a fire detection terminal installed in a warning area is received, the receiver starts calling and scanning the terminal, and the terminal that issued the alarm The present invention relates to a fire alarm system that transmits and displays on a receiver the address of the terminal and the temporal changes in physical phenomena caused by a fire detected by the sensor section of the terminal when a call is received.

Conventionally, fire alarm equipment that divides one-time changes in smoke density temperature, etc. caused by a fire detected by the fire alarm unit 4 into multiple detection stages and transmits them to the receiver side has been used, for example. A plurality of terminals each having a fire sensor section are connected in parallel to a pair of power supply signal interrogators, and a calling scan is performed in which the receiver regularly calls the plurality of terminals cyclically and sequentially. ,rt.m''”nallthH・
The data corresponding to the detection stage of the "ゞ゛" section is sent to the receiver, and the reception 41'l (reads the address 7N of the terminal that sent the data by counting the ringing signals in l'ill, etc.)
The stage of the fire and the address of the terminal device are displayed based on data reception (Japanese Patent Laid-Open No. 53-60468).

In addition, other conventional devices include Ichigen Kinu and control from the receiver to the terminal! tlOta individually, and in the same way, the receiver calls multiple terminals cyclically and sequentially with coded decoded codes using the control function. When the terminal that has detected a fire is called, the stage of the fire is determined. A proposal has been made to send the displayed data to the receiver and display it together with the address of the terminal (Japanese Patent Laid-Open No. 53-47799).

However, all fire alarm systems use a method that constantly calls the terminal device, and the frequency of fire occurrence is extremely low, and the terminal device is constantly monitored cyclically in the steady monitoring state. However, since the calling circuit of the receiver and terminal device is always in operation, the current consumption increases, and the circuit elements that are always in operation deteriorate quickly, making it difficult to say that it is an effective monitoring method1. Furthermore, in the case of fire alarm equipment, multiple terminals are connected to a pair of signal lines, and any terminal may emit a signal. l? L
Even if data signals are being transmitted and received between the terminal and the receiver, the fire sensor sections of not only the alarming terminal but also all other terminals always receive a normal monitoring voltage.1. Continuing from 1st view,
However, in the case of conventional systems, means for maintaining and continuing the monitoring status of these terminals have not been disclosed.

The invention was made in view of these conventional problems, and detects changes in the surrounding physical phenomena caused by a fire in multiple stages between a pair of power and signal lines drawn out from the receiver. A fire alarm system in which a plurality of terminal devices each having a sensor section that outputs a signal are connected in parallel, and the terminal device sends fire detection information based on the detection signal of the sensor section and address information of the terminal device as a data signal to a receiver. In the steady monitoring state, the receiver stops calling and scanning, and the receiver only starts scanning when it receives the "Shihakusho" signal that is sent when the sensor section of the terminal detects a fire. When the terminal device that sent the alarm signal is called, the receiver stops the paging scan.
In this stopped state, the terminal device sends a data signal consisting of fire detection information and address information set to the terminal device to the receiver for optical indication processing, and after receiving the data, it is called again and data transmission 1 indication processing is performed. By repeating this, cyclic calls in the steady monitoring state are no longer necessary, which greatly reduces current consumption, and any terminal can issue an alarm.
Even when data signals are being sent and received between the terminal device and the receiver, the fire sensor section of not only the alarming terminal device but also all other terminal devices will always receive normal monitoring voltage and continue monitoring. The purpose is to provide highly reliable fire alarm equipment that makes it possible to

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

FIG. 1 is a block diagram showing the basic structure of the present invention.

First, to explain the configuration, 1 is a fire receiver, and from the fire receiver 1, a pair of power supply signal wires consisting of a combination of 1m#L*, Lm...Ln and a common line C are connected to a plurality of signal wires. It can be drawn out for each warning area, and as shown in HL 1 as a representative, a detection signal is output in multiple stages between 1liL t and the common line C according to changes in the surrounding physical phenomenon caused by the fire. Sensor parts 2a, 2b.

...2n are connected in parallel, and these sensor parts 2a and 2b.

...2! Terminals 3a, 3b,
...3n are connected in parallel, and the line is further connected,
A terminating resistor 4 for detecting disconnection is connected to the terminal end of the common line C.

♂ Senna unit 2 that outputs multi-stage fire detection signals
For example, in the case of detecting smoke from a fire, first, second, and third detection sensitivities are set for ordinary smoke detectors, and smoke? l! IV
The detection signal of the first type sensitivity, the detection signal of the second type sensitivity, and the detection signal of the third type sensitivity are output in multiple stages according to the increase in the sensitivity.

FIG. 2 is a circuit block diagram showing the specific configuration of the terminal devices 3a to 3n, which are compatible with the embodiment shown in FIG. 1, together with a sensor section.

First, to explain the configuration, the terminal device 3 is connected via the diode bridge 5 between the line Ln and the common #(C).
The voltage obtained through the diode bridge 5 is supplied from the constant voltage circuit 6 to each circuit section as a power supply voltage.1. ing.

The detection output of the first stage of the sensor section 2 having one to three types of detection sensitivities, that is, the detection output with the first type sensitivity having the highest detection sensitivity, is given to the alarm signal output circuit 7 via the monostable multivibrator 14c. The alarm signal output circuit 7 receives the detection signal from the sensor section 2 through the diode bridge 5, and outputs the signal between the circuit and the common #C.
Stable multi-by-break 1 due to the impedance of I
4c is short-circuited for an operating time of, for example, 100 m5ec, and the alarm signal n is sent to the receiver.

Circulation flowing through the line Ln by the signal sent out by the first impedance of the signal output circuit 7
, for example, l, = 20 mA.

The value of the current l caused by sending out this signal is determined by the total amount of consumption and current in the steady monitoring state of multiple terminals connected to line Ln. It is being

On the other hand, an ejection signal detection circuit 8 is provided to detect a ringing pulse signal sent from the receiver in order to ring the terminal, and this ejection signal detection circuit 8 detects the voltage of the line Ln by the ringing pulse from the receiver. Since the signal is a pulse signal that varies between 20V and 30V, the calling signal is detected and output based on a voltage change of the line Ln, which is, for example, about 7V or more.

Furthermore, in order to prevent false detection due to noise superimposed on the line LnK, for example, if the calling pulse signal from the receiver is a pulse signal of $10m5ec with a duty ratio of 50% and 20m5ec per cycle, 5. m
It is configured so that only signals with a pulse width of 5 ec or more are detected as a calling pulse signal.

The ringing pulse signal from the receiver detected by the ringing signal detection circuit 8 is given to the reset release circuit IO and the counter circuit 11 via the pulse delay circuit 9. The counter circuit 11 and the decoder circuit 16 are activated by the first ring pulse detected, and the reset state of the counter circuit 11 and the decoder circuit 16 are completely released. Therefore, the counter circuit 11 starts counting operation from the second ring pulse signal/signal detected by the ring signal detection circuit 8. It becomes stone-like.

The counter circuit 11 sequentially outputs the count value of the calling pulse signal to the address setting circuit 12, and compares the count value of the counter circuit 11 with the address code of the terminal device 3 preset in the address setting circuit 12 of 13 matching circuits. , a coincidence output is generated on the condition that a detection signal is output from the sensor section 2 when the two match.

The output of the matching circuit 13 is the monostable multivibrator 14
a and 14b, and the monostable multivibrator 14a generates an output to operate the switch circuit 17 and supply the A/D conversion circuit 18 with the υ power supply voltage from the constant voltage circuit 6 to enter the operating state. , converts a detection signal according to the detection sensitivity of the sensor unit 2 into a digital signal and outputs it. At the same time, the monostable multivibrator 14b outputs an output to activate the oscillation circuit 15, and the oscillation pulse of the oscillation circuit 15 (,
The decoder circuit 16 generates a pulse output that is sequentially shifted to the output terminal in synchronization with the oscillation pulse of the oscillation circuit 15, and outputs the first terminal output to the OR circuit 19. It is applied to the data signal output circuit 21 as a start signal in synchronization with the oscillation pulse from the AND gate 20 through the AND gates 22a to 22.
The conversion output of the AD conversion circuit 18 for 2nK, that is,
Fire data corresponding to the detection signal of the sensor section 2 is sequentially sent out as fire detection information via the OR circuit 19 and the AND gate 20, and an address code preset for the terminal device 3 is sent to the data setting circuit 22. OR circuit 19,
The final terminal output of the decoder circuit 16 is outputted from the OR circuit 19 and the AND gate 20 as an end pulse.

In this way, the shift output of the decoder circuit 16 provides start pulse fire detection information, address code and "7 de/<
py X,, f/<312 Column is data' signal amount
.

By short-circuiting the line Ln by the second impedance according to the pulse train generated by the power circuit 21, a data signal is transmitted to the receiver.

The data signal is transmitted by the data signal output surface path 21, and the line current I flowing through the circuit iLn due to the second impedance is, for example, I =:= 10
0 to 200mA (However, the following explanation is
A), and therefore the transmission of the data signal is omitted in the current mode.

FIG. 3 is a circuit diagram showing an embodiment of an interface circuit provided at the input stage of the receiver l in the embodiment of FIG. 1. By providing the interface circuit of FIG. Even if the functions of the system are computerized, consideration has been given to ensuring that the number of input ports to the computer does not increase significantly due to an increase in the number of lines.

First, to explain the configuration, the rotation iL in the steady monitoring state
The 24V supply voltage to n is connected to resistor R1 and diode D6.
A circuit equipped with a transistor Q1, bias resistors R1 to R3, and a capacitor C1 is installed as a current detection circuit to detect the line current I = 20 mA due to the alarm signal sent from the terminal when a fire is detected. When the warning signal is sent, the voltage generated across the resistor R turns the transistor Q on and conductive, and the collector of the transistor Q is connected to the resistor R4 and the diode D! is outputted to the receiver side as a representative fire signal E1 via
Further, the collector output of the transistor Q1 is directly taken out to the receiver side as a line fire signal Bln via a resistor R4.

Further, the collector of transistor Q is connected to the base of transistor Q, which has a base bias circuit made up of resistors R and R6, and conduction of transistor Q1 makes transistor Q conductive, and resistor R2°R13 and transistor Q are connected to the base of transistor Q. The structure is such that the transistor Q is self-maintained by the flowing current.

Further, the interface circuit is provided with a constant voltage circuit consisting of a Darlington-connected transistor QmeQrv, a resistor R1゜, and a Zener diode ZD. A constant voltage output of 20V is based on the Zener voltage, and in the steady monitoring state, the supply voltage of diode D is 24V, which is higher than the constant voltage output of 20V, so diode D is turned off and the constant voltage is output. No output is provided.

Further, a transistor Q is connected in series with the Zener diode ZD via a diode D, and this transistor Q
, in the steady monitoring state, the resistors R, , R, , the diode Da and the resistor R1! The transistor Qs is turned on by the base voltage given by the base bias circuit consisting of
, Q, and Ma are in the operating state.

1 Next, when the transistor QI is turned on by receiving the good news signal, the representative fire signal E, t is outputted via the diode D.
Terminal ringing signal E outputted from the receiver side based on tc
cn is connected to the base of transistor Q1 via resistor R1, and since this terminal calling signal Ecn is a pulse signal with a constant period, transistor Q8 is turned on and off by terminal calling signal BCnlC, and transistor Qs
The collector of - is connected to the transistor Q through the diode Ds.
When transistor Q3 is turned on, transistor Q4 is turned off, and when transistor Q3 is turned off, transistor Q4 is turned on.
When the transistor Q4 is off, the constant voltage circuit including the transistors Q-, Q, and v repeatedly operates and stops, and when the transistor Q4 is on, the constant voltage circuit outputs a constant voltage of 20V, but when the transistor Q4 is turned off, the Zener die □・・Since the setting of the reference voltage by the 1-ohde ZD is canceled, the transistors Q e and Q t are turned on only by the bias from the resistor R1, and the power supply voltage 30 supplied through the resistor n.
The configuration is such that V is superimposed on the line Ln via a resistor R.1. and a diode Dv.

Therefore, when the terminal calling signal Ecn from the receiver is input to the interface circuit, the constant voltage operation and non-constant voltage operation of the constant voltage circuit are repeated by turning on and off the transistor Qs and turning off and on the transistors Q and 4. #Ln
The voltage starts to change in a pulse-like manner in the range of 20V and 30V. Note that the transistor Q is turned on by the alarm signal from the terminal. On the other hand, due to the load current flowing through the resistors R, , R, to the terminal, the anode side voltage of the diode D decreases, and the voltage supplied to the line Ln via the diode D is changed to a constant voltage circuit equipped with transistors Qs-Qy. The output voltage is 20V or less.

Further, the interface circuit is provided with a current detection circuit for detecting data signals consisting of a transistor Q and a resistor R' 11, as a circuit for detecting data signals sent in current mode by a terminal called by a receiver. The resistance RIs is a small resistance of, for example, about 2Ω, and the line current I = 200mA flows due to the transmission of data signals from the terminal.
The voltage generated across resistor R1 only for transistor Q
Il is turned on, and the data signal Bd is output to the receiver side via the resistor R and the diode D connected to the collector of the transistor QI.

Furthermore, the collector of the transistor Q for data signal detection receives a trouble signal I! due to a line short circuit via the diode D. +4, and the anode side of diode D is connected to resistor Rffi, capacitor C.
3 is connected, the capacitor C is charged after a certain period of time that is longer than the reception time of the data signal from the terminal after the transistor Q is turned on, and when the voltage reaches a certain voltage, the diode D is charged. Line short circuits are detected from the output.

Also, the connection point between the resistor RtI and the capacitor C6 is the resistor 2! and is connected to the pace of the transistor Q4 via the diode D8, and when a line short circuit trouble is detected t7, the transistor Q4 is turned on, and the transistor Qs,
Forcibly create a constant voltage circuit consisting of Qy! 11I, the supply voltage of 30V required for sending the data signal from the terminal is 20V.
The voltage is lowered to a constant voltage of V to prohibit the transmission of data signals.

In addition, the transistor Q, which is connected in parallel to the constant voltage circuit consisting of nine transistors, turns on when the current flowing through the fflAlIn exceeds 300 mA, and cuts off the transistors Q, Q, and Q. It constitutes a circuit.

Of course, the interface circuit shown in the third factor is the circuit I in FIG.
Although provided for each of RL t to Ln, each output of the short-circuit triple E4d1 representative fire E is connected to the same line as the other interface outputs.

FIG. 4 is a circuit block diagram showing a specific embodiment of the receiver 1 in the embodiment of FIG. 1 together with the interface circuit shown in FIG. 3.

First, to explain the configuration, the ink face circuit 24 is as follows.
Interface circuit 24a~ for each name/line line ~/Ln
24n, and each ink face circuit 2
The representative fire signals E1 of 4a to 24n are compiled and output, and the line fire signals El+ to Eiln are taken out to each interface circuit 24a to 24n 9i, and further to each interface circuit 11 of terminal device calling signals Ecl to Ecn.
A terminal is provided for each of the M circuits 24a to 24n, and furthermore, a terminal is provided so as to output the data signal Rd received by line operation to the receiver side.

The representative fire signal from the interface circuit 24 is inputted to each of the monostable multivibrator 25 and the delay circuit -29, and the representative fire signal E1 is outputted from the monostable multi-pipe rake 25 (Oagoo) 26,4.
The decoder 27, the counter 43, the counter 51, and the latte circuit 48 are reset through the circuits 6.47 and 53, respectively.

The output of the delay circuit 29 into which the representative fire signal E is input is connected to an oscillation circuit 32 via an AND gate 31, and this oscillation circuit 32 is activated when it receives the representative fire signal E3, that is, an alarm signal from the terminal device. Outputs oscillation pulses to sequentially scan the line.

The output of the oscillator circuit 3'2 is reflected in the decoder 27, and the decoder 27 sequentially generates a 1-level output at the output terminals Q, .

Note that the final output terminal Qn of the decoder 27 is given to the monostable multi-bi break 28, and the terminal Qn of the decoder 27
The number of terminals up to = 1 corresponds to the number of lines, ~Ln, and when the final output terminal Qn becomes H level, the output of the monostable multivibrator 28 passes through the OR gate 26 and resets the decoder 27. .

Each of the output terminals Q1 to Qn-1 of the decoder 27 has a number of AND gates 33a corresponding to the lines Ll to Ln.
~ 33n, and the other of the AND gates 33a to 33n receives the line fire signal gJ from the interface circuit 24.
l=Eln is input.

Therefore, Antogame) 33a-33n is decoder 2
When the fund gate inputting the line fire signal is selected by the output of 7, the selected AND gate produces an H level output.

The outputs of the AND gates 33a to 33n are input to the NOR gate 36, and the output of the NOR gate 36 is given to the oscillation circuit 32 via the OR gate 30 and AND gate 31 tube, and the H level output of any of the AND gates 33a to 33n causes the OR gate to be activated. 36 produces an L level output, the OR gate 30
The AND gate 31 is disabled through
Stop the second oscillation. Further, the output of the NOR gate 36 is sent to the oscillation circuit 4 via an inverter 37 and an AND gate 39.
0, the other side of the AND gate 39 has a latch circuit 4 that latches the start pulse of the data signal Ed.
The output of 8 is given via the inverter 38, and at the same time when the oscillation circuit 32 stops oscillating due to the L level output of the NOR gate 36, the AND gate 39, which is in an allowable state due to the H level output of the inverter 38, outputs the H level of the inverter 37. The output operates the sizing circuit 40.

This oscillation circuit 40 is used to send a paging pulse signal to a plurality of terminals connected to the line selected by the output of the decoder 27 when the oscillation line 32 is in a stopped state.

(1, that is, the output power of the oscillation circuit 40 is
AND gate 42a provided for each -Ln
' to 42n, respectively, and
Since any one of a to 42n is in the permissible state with the output of the judgment terminal of the decoder 270 due to the stop of the oscillation M path 32, a terminal device call is made to any of the selected lines via the AND gate in the permissible state. A signal, that is, an oscillation pulse of the oscillation circuit 40 is output.

When the terminal device detecting fire y responds to the call by calling the terminal device by the oscillation pulse of the numbering circuit 40 and outputs a data signal, the data signal Ed received by the interface circuit 24 is sent to the latch circuit 48 and It is configured to be applied to each of the serial-parallel conversion circuits 55.

The latch circuit 48 receives the first received data signal P]d
The start pulse of the oscillation circuit 40 is stopped by setting the start pulse to 2×L, and inverting this ratte output to the L level by the inverter 38 and disabling the AND gate 39. During this period, the oscillation circuit 40 stops calling the terminal.

Further, the output of the two-way circuit 48 is configured to operate an oscillation circuit 50 via a delay circuit 49, and the oscillation pulse of the oscillation circuit 50 is sent to the serial-to-parallel converter circuit 55 as a clock pulse. 55 to interface circuit 24
Parallel data signals consisting of input pulse trains
The converted data is output to a processing circuit 60 for converting the data into data and displaying the fire detection stage and address based on the received data.

Further, the output of the oscillation circuit 50 is given to a counter 51, and a count value corresponding to the number of pulses of the received data is set in the counter 51. When the counter 51 reaches a full count, reception of the data signal Bd ends. The output of the monostable multivibrator 52 is used to reset the latch circuit 48 via the OR gate 47, and the output of the monostable multivibrator 52 is applied to the counter 51 itself via the OR gate 53. I'm trying to reset it.

A latch circuit 48 based on the count output of this counter 51
The reset causes the fr oscillation circuit 40 to resume its oscillation operation, having stopped its operation by the double output of the latch circuit 48.

On the other hand, an oscillation circuit 40 that outputs the ejection pulse signal of the terminal device
The output of counter 43 is given to counter 43.
3 is set with a count value corresponding to the number of terminals connected to the line, and when the count value of the counter 43 reaches the set count, the monostable multivibrators 44 and 45 are sequentially operated and the counter 43 is activated. At the same time, the stopped oscillation circuit 320 is restarted via the OR gate 30 and the 7-band gate 31, and the line scanning by the decoder 27 is started again.

Next, the operation of the embodiment of the present invention shown in FIGS. 2, 3 and 4 will be explained with reference to the time chart shown in FIG.

The interface circuit 24 of the receiver l shown in FIG.
Let us take as an example a case where the number of lines L1 to Ln that have been drawn out is 10, and 10 terminals are connected in parallel to each line.

In the steady state/monitoring mode, the resistance B of each interface circuit shown in Fig. 3, ! A power supply voltage of 24 V is supplied to the line Ijto via the diode D and the line Ijto.

In this state, for example, the controller of the #2 terminal (address code 000010) connected in parallel to the 5th line L@ detects a fire and outputs a first-stage fire detection signal with type-1 sensitivity. Assuming that, depending on the detection signal of the sensor section 2 in the terminal device shown in Fig. 2, the operating time of J, monostable multivibrator 1.4,
The line is short-circuited via the diode bridge 5 by the first impedance, and a line current I=20 mA is caused to flow, thereby sending an alarm signal to the receiver.

Due to the alarm signal sent from the terminal device, an air current of 20 mA due to the output of the alarm signal flows through the resistor R1 of the interface circuit shown in FIG.

Transistor Q is turned on by the voltage generated in , and outputs representative fire signal EI through resistor R4 and diode D, and also outputs line fire signal Eno1 indicating that line L1 is in a fire detection state. , transistor Q is also turned on by turning on transistor Ql, and transistor Q is kept in the on state.

The representative fire signal E, detected by the interface circuit by receiving the alarm signal from the line, is given to each of the monostable multivibrator 25 and delay circuit 29 of the receiver shown in FIG. Stable multi, output of vibrator 25 to OR gates 26, 46, 47 and 53
Decoder 27, counter 43, latch circuit 48 via
and the counter 51 to release the respective reset states.

After this reset is released, the extension circuit 29 generates an H level output, and the H level output of the NOR gate 36 causes the OR gate 3
Antagonist 31, which is in the allowable state via 0, generates an H level output and activates the oscillation circuit 32 to 1.

The operation of this oscillation circuit 32 causes oscillation pulses to be sent to the decoder 2.
7, and the decoder 27 receives AND gates 33a, 33b, .
The line fire signal E-no-betsu is input to 5.
The decoder output to the 5th AND gate causes the 5th AND gate to output an H level, so that the output of the OR gate 36 falls from the H level to the L level. Therefore, the AND gate 31 is inhibited by the L level output of the NOR gate 36 via the OR gate 30, and the oscillation circuit 3
2 stops the operation after outputting the fifth oscillation pulse.

On the other hand, the L level output of the NOR gate 36 is output to the inverter 37.
The output of the inverter 38 goes to H level and is applied to the oscillation circuit 40 via the AND gate 39 in a permissive state, and the oscillation circuit 4o starts the oscillation t1r operation.

AND gates 42a and 42b provided corresponding to the number of lines via the oscillation pulsed OR gate 41 of the oscillation circuit 40
, . . . , and the 5th AND gate is output from the decoder 7 and the line fire signal (AND) 33a, 33b, . This 51
The oscillation pulse of the oscillation circuit 40 is outputted to the interface circuit 24 via the F-th AND gate as the terminal discharge signal EC3 for the corresponding line LI.

In this way, the terminal device calling signal Ec outputted to the interface circuit by the oscillation pulse of the oscillation circuit 40 in FIG. 4 is transmitted by the transistor Q1 of the interface circuit in FIG.
, the oscillation pulse turns on the transistor Q,
At the same time as transistor Q3 turns on and off, transistor Q4 turns on and off, and transistor Q4 turns on and off.
When the zener diode ZD is turned off, the connection of the Zener diode ZD is cut off, and the constant voltage path consisting of the transistors Qs and Qy supplies a voltage of 30 V to the line via the diode D.
On the other hand, when the transistor Q4 is turned on, a constant voltage output of 20 V based on the Zener diode Z1 is sent to the line.

That is, based on the input of the terminal calling signal Bc6 from the receiver, the interface circuit uses the constant output voltage of 20V as a reference level to rise to 30V.
Superimpose the ringing pulse 2 signal with a voltage change of V.

+1 The voltage mode calling pulse signal thus superimposed on the line LL+ from the interface circuit is sent to the signal output circuit 7 at P1131 by the detection signal from the sensor unit 2 shown in FIG.
is detected by the calling signal detection circuit 8 of the terminal device 3 which operates the 1F1 signal, and passes through the pulse delay circuit 9.
The reset release circuit 1 is activated by the ejection pulse signal detected first.
0 is activated to release the reset of the counter circuit 11 and the decoder circuit 16, and then when the second ring pulse is issued, this ring pulse is counted by the counter circuit 11, and in the matching circuit 13, the address is It is compared with the setting address code assigned to the second terminal device, which is preset in the setting circuit 12.

In this case, since this is the second terminal device, the address setting circuit 12 is set with a binary code that is "2" in 110 degrees, and therefore the counter circuit 11 counts the third calling pulse signal. The matching circuit 13 determines that the count output when counting 2 matches the set address of the address setting port 1 path 12, and the monostable multivibrator 14a.

14b. In response to the output of the matching circuit 13, the stabilizer multivibrator 14a outputs an output to activate the switch circuit 17, and the constant voltage output of the constant voltage circuit 6 is supplied to the AD conversion circuit 18, which is detected by the sensor section 2. (However, the number of AND gates depends on the AE conversion circuit.) (corresponding to a bit number of 18).

Subsequently, the monostable multivibrator 14b generates an output to operate the oscillation circuit 15, and the oscillation pulses of the oscillation circuit 15 are input to the decoder circuit 16, which sequentially outputs pulse signals to the output terminals of the decoder circuit 16. Therefore, the sequential output of the decoder 16 causes the OR circuit 19 to generate a start pulse, AD
The pulse representing the fire detection stage of the conversion circuit 18, the address code of the terminal device 3 set in advance in the data setting circuit 22, and the end pulse are sequentially output, and the OR circuit 1
The pulse train from 9 is sequentially sent to the data signal output circuit 2 by the acid gate 20 in synchronization with the oscillation pulses of the oscillation circuit 15.
1 is given.

Here, the pulse string given to the data signal output circuit 21 is, for example, '1100000010 space 1', the first pid is a start pulse,
The next 3 bits represent the fire detection stage, the next 6 bits are the address data, and the final bit after the 9 spaces is the end pulse.

Data signal output circuit 21 AND gate 20 For the pulse train given, a pulse corresponding to bit "1" is connected to the line, and short-circuited by the second impedance, and the line L m K I is short-circuited by the second impedance.
A line current in the range t = 100 to 200 mA, for example I* = 200 mA, is applied to send the data signal to the receiver in current mode.

When the terminal sends a data signal to the receiver in this way,
In the interface circuit shown in Fig. 3, I = 100 to 2 due to the first start pulse by sending the data signal.
A line current of 00mA flows, and this line current causes the resistance R to
The voltage developed at I turns on transistor Q, and outputs a start pulse reception signal to the receiver circuit of FIG. 4 via resistor R0 and diode D1. The reception signal of this start pulse is launched by the latch circuit 48 of the receiver circuit in FIG. Stop operation.

That is, the oscillator circuit 40 is connected to the line 2
Data signal (□・ ) when calling the th terminal.

Tsu,□□J　nt□O.

Note that the output of the oscillation circuit 40 is fixed at H level when the oscillation operation is stopped.

Therefore, when the oscillation circuit 40 stops oscillating, the pace input of transistors Q and s in the interface circuit of FIG. As a result, Zener diode ZD is disconnected and transistor Q
The constant voltage function of , ,Q is lost, the supply voltage to the line is set to 30V, and the open line voltage through which data is sent from the terminal is kept at 30V.

On the other hand, the launch output of the start pulse latched by the launch circuit 48 in the receiver circuit of FIG. Serial-to-parallel conversion circuit 5
5 to convert it into parallel data and output it to the processing circuit 60,
As shown in the time chart of Figure 5, this data signal is the first signal from the fire detection information because the fire detection information is ``100'' and the address information is 000010.
It determines and displays that it is in the fire detection stage, and also displays that the fire has been detected by the #2 terminal on the line based on the address information. Also, the serial-to-parallel conversion circuit 5
The oscillation pulses of the oscillation circuit 50 for 5 are counted by a counter 51, and when the oscillation pulses corresponding to the number of received pulses of the data signal are counted, the counter 5 outputs an output to the monostable multivibrator 52 via the OR gate 47. The latch circuit 48 is reset.

In addition, a monostable 1 lute biprator 54 and an or gate 53
After a certain period of time, the counter 51 and the serial-to-parallel converter circuit 5
5 are also reset.

When the latte of the latte circuit 48 is reset, the output of the inverter 38 becomes H level, the AND gate 39 produces an output, and the oscillation circuit 40, which is in a stopped state with an H level output,
The oscillation operation of the oscillator is restarted, and the calling pulse signal for the circuit eLy is sent out again.

In this way, when the number of paging pulse signals generated by the oscillation circuit 40 reaches the number of Rxo terminals provided on the line, the counter 43 generates an output and sequentially triggers the monostable multivibrators 44 and 45. After a certain period of time, the counter 43 is reset via the OR gate 46, and the '5th line is reset via the OR gate 30 and the AND gate 31.

The oscillation circuit 320, which had been in a stopped state, resumes its oscillation operation during the line scanning for the remaining lines, and the line scanning for the remaining lines ~L16 is continued for a long time.

When scanning of all lines is completed by this oscillation circuit 320 line scanning, the monostable multivibrator 28 is triggered by the output of the final terminal Qn of the decoder 27, and the OR gate 26
The decoder 27 is reset via the next oscillation circuit 3.
When the oscillation pulse from No. 2 is received, the line is connected again, line scanning is started from then on, and the above operation is repeated in the same manner.

In addition, although the above embodiment is based on the case where the sensor section of the terminal unit outputs a fire detection signal with three sensitivities, the present invention is not limited to this and can be applied to any multiple stages. The detection sensitivity may be used to detect temporal changes in surrounding physical phenomena caused by a fire.

As described above, according to the present invention, the sensor unit outputs a detection signal in multiple stages between the pair of power supply signals #1 drawn out from the receiver in accordance with changes in surrounding physical phenomena caused by a fire. In a fire alarm system, multiple terminal devices with a In this case, paging scanning from the receiver is stopped, and the receiver starts cyclic paging scanning of the terminal device only when it receives an alarm signal sent when a fire is detected by the sensor section of the terminal device. When the terminal device that sent the alarm signal is called, the receiver stops calling scanning, and in this stopped state, the terminal device sends a data signal consisting of fire detection information and address information set to the terminal device to the receiver. After receiving this data, the call is restarted and the above operation is repeated, so that when the terminal device is in a steady monitoring state where fire detection is not performed, the terminal device is not detected by the receiver. The device's paging scanning is stopped, and the terminal device is only supplied with power from the receiver's power supply, which eliminates the conventional device that constantly performs cyclic storage and output scanning of the terminal device. The current consumption in the receiver and terminal device can be significantly reduced compared to the previous model, and the circuit for scanning calls in the receiver and in the terminal device can be decoded to detect fire detection signals. Since the circuits that send out the presence/absence signals are not in constant operation, deterioration of the circuit elements that make up these circuits is greatly reduced, making it possible to obtain fire alarm equipment with excellent durability and reliability. Effects can be obtained.

On the other hand, when a fire is detected in the sensor section of one of the terminals, the receiver starts calling scanning of the terminal by receiving the 11 signal sent from the terminal. If the power supply voltage supplied to the terminal is set at a predetermined voltage level, for example, if the power supply voltage in the steady monitoring state is 24V, it will be 30V, and the terminal is set in voltage mode by sending a ringing pulse signal with voltage level changes. This call signal is determined only by the terminal device that detects a fire and sends out an alarm signal, and when it matches the preset call code, the detection stage is set to the front kana fire detection information and the terminal device. This data signal is sent out in a current mode, which is different from the call signal from the receiver that is sent out in voltage mode, and the data signal is sent out on the receiver side. Even if you perform reception processing, call a terminal device, and send out a data signal from the terminal device using the T-source signal line from the same receiver, the transmission mode of the calling signal and the data signal are different. , reliably prevents malfunctions due to mutual interference between the calling signal receiving system and the data signal receiving system, and also maintains constant voltage and current in sending out the calling signal in the voltage mode and sending out the data signal in the current mode. By setting the power supply voltage and monitoring current to a sufficiently high level in the monitoring state, the S/N ratio of the calling signal and data signal with respect to noise components is increased, and furthermore, the terminal device can be called and the data signal can be sent from the terminal device. Sometimes, when the power supply voltage from the transmitter to the terminal is higher than the normal monitoring state, the voltage drop due to the line impedance caused by the transmission of the call signal and data signal causes a significant drop in the power supply voltage to the terminal. This also has the effect that all terminal devices can operate stably at all times.

Furthermore, by providing a circuit on the receiver side that counts the oscillation circuit for the terminal ringing signal and determines which terminal is calling, and comparing it with the address information from the terminal, the It is good to be able to accurately determine the address of the terminal device.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the equipment configuration of the present invention, Fig. 2 is a circuit block diagram showing an embodiment of the terminal device in the present invention, and Fig. 3 is an example of an interface circuit used in the receiver of the present invention. FIG. 4 is a circuit diagram showing an embodiment of the present invention, and FIG. 5 is a circuit block diagram showing an embodiment of the receiver circuit according to the present invention.
The figure is a time chart diagram showing signal waveforms of various parts in the receiver circuit. 1...Receiver 2.2a, 2b, 2n...
・Sensor part 3.3a, 3b, 3n...Terminal device 4・
・Terminal resistance (1°"-1'-4k -)'7'lJ
y-) “°e @ m * m :# Do“8・
...Call signal detection circuit 11...Counter circuit 12.
... Address setting circuit 13 ... Matching circuit 15 ...
Oscillation circuit (for data transmission) 16... Decoder circuit 18... AD conversion circuit 23... Display circuit 24.24a-24n... Interface circuit 27.
... Decoder 32 ... Oscillation circuit (for line scanning) 40 ... Oscillation circuit (for calling signal) 48 River latch circuit 50 ... Oscillation circuit (for data reception) 55 ... Series-to-parallel conversion circuit 60・Processing circuit L, =Ln・
...Line C...Common line patent applicant Houteki Co., Ltd.

Claims (1)

[Claims] A plurality of terminal devices each having a sensor unit that outputs detection signals in multiple stages according to changes in surrounding physical phenomena caused by a fire are installed between a pair of power supply and signal lines opened from the receiver. In a fire alarm equipment that is connected in parallel and sends fire detection information based on a detection signal of a sensor unit and one address information of a nuclear terminal device from the terminal device as a data signal to a receiver, the terminal device includes the An alarm signal output circuit that short-circuits the signal line that also serves as the power distribution power supply for a predetermined time with a first impedance based on the detection signal of the sensor unit and sends an alarm signal to the receiver, and detects a calling pulse signal from the receiver. When the discharge signal detection circuit and the count value of the counter that counts the ringing pulses detected by the ringing signal detection circuit match the address information set in the terminal device, fire detection information based on the detection signal of one sensor unit and a data signal output circuit that converts a coded signal of address information of the terminal device into a pulse train, shorts the power supply signal line to a second impedance in response to the pulse train, and sends a data signal to a receiver; The receiver includes an alarm receiving circuit for receiving alarm signals from each terminal, and a ring pulse signal superimposed on the pressure supplied to the terminal by the received output of the alarm receiving circuit. A calling signal output circuit for outputting, a data receiving circuit for receiving a data signal from a terminal device, and a terminal device that outputs the stage of change of physical phenomenon due to fire and the data signal based on the data signal received by the data receiving circuit. and a voltage control circuit that maintains the voltage supplied to the terminal at a predetermined value higher than the supply pressure in the steady monitoring state while data is being received by the data receiving circuit. A fire alarm system characterized by: