JP2006004140A - Fire alarm system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a function from being stopped caused by a drop of a voltage in a sensor line by transmission of a common fire signal due to an alarm issue from a fire sensor connected to the same sensor line. <P>SOLUTION: This P type fire alarm system is connected with the plurality of fire sensors to the fire sensor line drawn out from a receiver. The fire sensor transmits the common fire signal 27 following an address signal 26, only for a fixed time, when detecting a fire to issue an alarm, and continues the transmission of the common fire signal after the lapse of the fixed time, when receiving a transmission continuing command signal 26 from the receiver. The receiver receives the common fire signal transmitted from the fire sensor in a unit of the sensor lines to issue the alarm, identifies the sensor, based on the address signal, and assigns the alarm-detected fire sensor address to output to the sensor line the transmission continuing command for continuing the transmission of the common fire signal, until the issued alarm detection number in the same sensor line reaches a prescribed number. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a fire alarm system in which a plurality of fire detectors are connected to a sensor line drawn from a receiver, and fire alarms are received and alarmed on a line basis.

  Conventionally, in the fire alarm system known as P type, a plurality of fire detectors are connected to the sensor line drawn from the receiver, and the alarm signal from the fire detector is received for each line. The fire is alarmed.

  On the other hand, in the fire alarm system known as the R type, a terminal device such as a repeater or an analog fire detector having a transmission function is connected to the transmission line drawn from the receiver, and when a fire is detected, for example, Based on the fire interrupt from the terminal device, issue the search command to identify the address of the terminal device that was issued, display the fire occurrence address, and collect and monitor the fire data from the identified terminal device Yes.

  Knowing the address of the fire detector or repeater that detected the fire in this way makes it possible to conduct appropriate evacuation guidance and extinguishment activities, and is an indispensable function especially for fire monitoring of large-scale facilities.

  However, in the P-type fire alarm system, the receiver knows which sensor line has fired, but which sensor out of the multiple sensors connected to the alarm line that has fired has fired. I don't know if I reported it.

  Therefore, in recent years, the P-type fire alarm system is also able to identify the fire detector that has been notified by transmitting an address signal from the fire detector that has issued the alarm. FIG. 11 is a time chart of a detector line voltage and a fire detector switching circuit when a fire is triggered in a conventional P-type fire alarm system.

  Of a plurality of fire detectors connected to the same sensor line, for example, if a fire detector with address 2 set as shown in FIG. By turning on the switching circuit provided in the fire detector that has issued the alarm, the alarm current as a common fire signal is caused to flow through the sensor circuit, and the voltage of the sensor circuit in FIG. Subsequently, as shown in FIG. 11C, when the fire detector set at address 3 is notified and transmits a common fire signal, the detector line voltage further decreases.

In the receiver, a common fire signal transmitted from the fire detector at address 2 that fired at time t1, that is, the alarm current that flows from the receiver to the fire detector is received and alarmed. If necessary, the fire detector address that has been issued is identified from the address signal received following the common fire signal, and necessary indications such as the area where the fire occurred are displayed.
JP 2001-184571 A

  However, in the P-type fire alarm system in which a common fire signal is transmitted from such a fire alarm that has been reported in the prior art, as shown in FIGS. When the fire detectors at address 7 detect fires one after another, they will send a common fire signal, the current flowing through the detector line will increase, and the power supply voltage supplied to the fire detector will increase. There is a problem that the fire detection operation and communication with the receiver become impossible.

It is an object of the present invention to provide a P-type fire alarm system that prevents a malfunction due to a decrease in sensor line voltage caused by transmission of a common fire signal due to a fire alarm connected to the same sensor line. To do.

  In order to achieve this object, the present invention is configured as follows. The present invention relates to a fire alarm system in which a plurality of fire detectors are connected to a sensor line drawn out from a receiver. When a signal and a common fire signal are transmitted and a transmission continuation command is received from a receiver, a notification control unit that continues to transmit a common fire signal after a lapse of a certain time is provided. The received common fire signal is received and alerted for each sensor line unit, and the reception control unit that identifies the sensor from the address signal and the number of alarms detected on the same sensor line until the predetermined number is detected. And a command output unit for outputting a transmission continuation command for continuing the transmission of the common fire signal by designating the detected fire sensor address to the sensor line.

  In this case, when the command output unit of the receiver receives a common fire signal received from the same sensor line, it designates the first sensor address and fires only from the first fire sensor. A transmission continuation command for continuing the signal transmission is output to the sensor line.

  In another embodiment of the present invention, in a fire alarm system in which a plurality of fire detectors are connected to a detector line drawn from a receiver, the fire detector is connected to another fire detector in the same sensor line. Until the number of alerts detected reaches the specified number, the address signal and the common fire signal are continuously transmitted when a fire is detected. After the number of alerts reaches the specified number, , Equipped with an alarm control unit that transmits an address signal and a common fire signal only for a certain period of time when a fire is detected, and the receiver receives the common fire signal transmitted from the fire detector for each sensor line. A reception control unit for alarming and identifying a sensor from an address signal is provided.

In this case, the alarm control unit of the fire detector transmits an address signal and a common fire signal only for a certain time when a fire is detected when the alarm detection of the same sensor line is the second and subsequent reports, for example. .

  According to the present invention, when a fire is detected, the fire detector is assumed to transmit a common fire signal following the address signal to the receiver only for a certain period of time. When a signal transmitted by fire detection is received from the detector, the address of the fire detector that issued the transmission continuation command signal is specified and output from the receiver, and this causes a certain period of time from signal transmission due to fire detection After that, the signal transmission is continued so that the fire detector that has issued the fire required for the P-type fire alarm system satisfies the requirement to continuously transmit the signal.

  For the third and subsequent reports, since the transmission continuation command is not output to the fire detector that has issued the alarm, signal transmission ends after a certain time. As a result, if the number of alarms for outputting the transmission continuation command is n, only the alarm current of the fire detector up to the alarm number n + 1 flows through the sensor line unless simultaneous alarms occur. It is possible to reliably prevent fire detection and communication with the receiver from being disabled due to a drop in the power supply voltage being supplied, thereby improving the reliability of the system.

In another embodiment of the present invention, the fire detector detects the number of reports on the same line. For example, until the second report, the fire detector continuously transmits a common fire signal following the address signal. After the bulletin, a common fire signal is sequentially transmitted following the address signal for a fixed time and stopped. As a result, if the number of reports that output a transmission continuation command is n, even if a plurality of fire detectors issue one after another, fires up to the number n + 1 of alerts will be detected on the sensor line unless they are triggered simultaneously. Only the alarm current of the sensor flows, and it is possible to reliably prevent the fire detection and the communication with the receiver from being disabled due to a decrease in the power supply voltage supplied to the fire detector, thereby improving the reliability of the system.

  FIG. 1 is an explanatory diagram of a fire alarm system according to the present invention. In FIG. 1, the sensor lines 2-1, 2-2,... N fire detectors 3 set with addresses 1 to n are connected together with a terminating resistor 4. The fire detector 3 connected to the sensor lines 2-1 to 2-m includes various types of fire detectors such as a photoelectric smoke detector, a thermistor heat detector, a differential detector, and a constant temperature detector. Can be connected.

  The receiver 1 is provided with an MPU 5 for the receiver, and an operation unit 7, an alarm display unit 8, a district display unit 9, a transfer output unit 10, and a memory 11 are provided for the MPU 5. In addition, receiving circuit units 6-1, 6-2,..., 6-m are provided on the sensor line side of the MPU 5 for each line, and each of the receiving circuit units 6-1 to 6-m has a sensor. Lines 2-1, 2-2 to 2 -m are drawn out.

  The fire detectors 3 connected to the sensor lines 2-1 to 2-m transmit a common fire signal following the address signal only for a fixed time T when a fire is detected. In the signal transmission at the time of the fire alarm, when a transmission continuation command is received from the receiver 1, the signal transmission of the common fire signal is continued even after a predetermined time T has elapsed.

  The receiving circuit units 6-1 to 6-m receive the address signal transmitted from the fire detector and the common fire signal from the change in the current flowing through the sensor lines 2-1 to 2-m, and output the received signal. To do.

  The MPU 5 of the receiver 1 is provided with functions of the reception control unit 12 and the command output unit 25. The reception control unit 12 sequentially reads the reception signal composed of the address signals of the reception circuit units 6-1 to 6-m and the common fire signal, identifies the sensor address for each line, and discriminates the common fire signal. Alarm display. As for this alarm display, a fire representative display and a district display (report line display) are displayed for the first report, and the number of reports and the sensor address are displayed for the second report and subsequent reports.

  The command output unit 25 designates the address of the fire detector that is transmitting the signal when the number of detected detections of the common fire signal received from the same sensor line reaches a predetermined number. A transmission continuation command is output to continue transmission of. In order to output this transmission continuation command, command output circuits 24-1 to 24-m are provided on the receiving circuit units 6-1 to 6-m, and corresponding sensor lines 2- 1 to 2-m, a pulse train transmission continuation command signal composed of a sensor address and a command code is output.

  Corresponding to the output function of the transmission continuation command by the command output unit 25 of the receiver 1, the fire detector 3 receives a common fire signal even if a predetermined time has elapsed when a transmission continuation command is received from the receiver 1. Is provided to continue the transmission.

  FIG. 2 shows an embodiment of the fire detector 3 of FIG. 1, taking a scattered light type smoke detector as an example. In FIG. 2, the fire detector 3 includes a rectifying circuit noise absorbing circuit 13, a switching circuit 14, a constant voltage / current limiting circuit 15, an operation indicator lamp 16, an address setting circuit 17, an alarm control unit 18 composed of a CPU, The oscillator circuit 19, the light emitting element 20, the light receiving element 21, the amplifier circuit 22, and the comparison circuit 23 are configured.

  Here, the rectifier circuit / noise absorption circuit 13 makes the current between the lines L and C nonpolar by using, for example, a diode bridge, a Zener diode, a capacitor, and further suppresses noise. The constant voltage / current limiting circuit 14 limits the supply current to the circuit section in the subsequent stage to a constant value in order to prevent a transient current on the lines L and C.

  During normal monitoring, the light emitting element 20 is pulse-driven by the oscillation circuit 19 to emit light periodically. When smoke is generated by a fire, light from the light emitting element 20 is scattered by the smoke and enters the light receiving element 21. The incident light is converted into a photocurrent, and after being amplified by the amplifier circuit 22, the signal is input to the comparison circuit 23.

  When this signal exceeds the specified value, the alarm control unit 18 counts in synchronization with the light emitting element 20 and transmits the signal to the switching circuit 14 when the predetermined count number is reached. The signal transmission by the notification control unit 18 transmits a common fire signal following the address signal only for a fixed time T when a fire is detected and the alarm is issued. When a transmission continuation command is received from the receiver 1, a common fire signal is continuously transmitted even after a predetermined time T has elapsed. The switching circuit 14 is switched in response to a signal from the alarm control unit 18 and causes an alarm current as a fire signal common to the address signal to flow between L and C of the sensor line. Also, the alarm control unit 18 turns on the operation indicator lamp 16 at the same time.

  FIG. 3 is an explanatory view showing the first embodiment of the present invention by taking out one of the sensor lines of FIG. In FIG. 3, the sensor line 2 drawn from the receiver 1 has no. 1-No. A fire detector 3 in which sensor addresses 1 to n indicated by n are set is connected. For the fire detector 3, an alarm control unit 18 and a switching circuit 14 are shown. The switching circuit 14 has a resistor R 1 and a transistor Q 1 connected in series between the detector lines 2.

  The receiver 1 includes a receiving circuit unit 6 and a command output circuit 24. The power source + Vcc power line in the receiver 1 is connected to the L side which is the plus side of the sensor line 2 via the receiving resistor R2, and supplies the power source voltage to the sensor line 2. The transistor Q2 provided at the output of the command output circuit 24 is connected in series with the output resistor R3, and this series circuit is connected between the sensor lines 2.

  The alarm control unit 18 of the fire detector 3 sequentially transmits an address signal and a common fire signal only for a predetermined time T when a fire is detected and notified. Further, when receiving the transmission continuation command from the receiver 1, the alarm control unit 18 continues to transmit a common fire signal for a certain time T.

  The receiving circuit unit 6 of the receiver 1 receives an address signal and a common fire signal transmitted from the fire detector 3 connected to the detector line 2 to generate a reception output, and this reception output is the MPU 5 in FIG. Are received by the reception control unit 12 and fire reception control is performed.

  In the fire reception control by the reception control unit 12, a common fire signal transmitted from the fire detector 3 is received and alarmed for each sensor line, and the fire detector is identified from the address signal. In this case, when receiving the first report, the representative fire display and the area display corresponding to the sensor line are displayed, and from the second report onward, the number of reports and the sensor address are displayed.

  Further, the command output unit 25 of the receiver 1 detects the number of reports on the sensor line 2, and until the number of reports reaches a predetermined number, for example, the second report, the fire detector address that issued the report. And a transmission continuation command for continuing transmission of the common fire signal is output to the sensor line 2. In order to output a transmission continuation command according to an instruction from the command output unit 25, the receiver 1 is provided with a command output circuit 24, which transmits a pulse signal including a sensor address and a command code by turning on and off the transistor Q2. A continuation command is output to the sensor line 2.

  FIG. 4 is a time chart showing the signal transmission operation at the time of fire alarm in FIG. 3, taking as an example the case where fire detection is performed in the order of the fire detectors at address 2, address 3 and address 5. 4A shows the sensor line voltage, FIG. 4B shows on / off of the transistor Q2 of the command output circuit 24 provided in the receiver 1, and FIGS. 4C, 4D, and 4E. ) Indicates ON / OFF of the transistor Q1 provided in the fire detector 3 at addresses 2, 3, and 5.

  In FIG. 4, when the fire detector at address 2 first detects a fire at time t1, an address signal 26 indicating address 2 is transmitted by turning on and off the transistor Q1 of the switching circuit 14. When the address signal 26 is transmitted, the common fire signal 27 is transmitted, that is, the transistor Q1 is turned on.

  Here, in the fire detector 3 of the present invention, when the transmission continuation command signal is not output from the receiver 1, for example, as shown in the time chart of FIG. When a fire is detected in FIG. 5B, the fire signal 27 common to the address signal 26 is transmitted only for a predetermined time T as shown in FIG. 5C, and then the signal transmission is stopped. This also applies to the fire detectors at addresses 3 and 5.

  As described above, in the present invention, the basic function of transmitting and outputting a common fire signal following the address signal only for a predetermined time T when a fire is detected in the fire detector is shown in FIG. B) When the receiver 1 receives the address signal 26 and the common fire signal 27 from the fire detector of the address 2 at the receiver 1, the first signal is received, so that the address 2 at the time t2 is received. The fire detector is designated and a transmission continuation command signal 28 is output to the detector line 2 by the operation of the command output circuit 24.

  When this transmission continuation command signal 28 is received and decoded by the fire detector of address 2 in the fire detection state, the signal transmission is not stopped when a certain time T1 has elapsed from time t1, and the common fire signal 27 is continuously transmitted. Keep doing.

  Even when the fire detector of the address 3 fire detector is detected at the time t3, the common fire signal 30 is transmitted after the address signal 29, and the fire detector is receiving the second signal. At t4, the fire detector at address 3 is specified and a transmission continuation command 31 is output. Upon receipt of this, the fire detector at address 3 continuously outputs the common fire signal 30 even after a predetermined time T has elapsed from time t3. Continue to send to.

  Further, when the fire detector at address 5 performs fire detection at time t5, the fire signal 33 common to the address signal 32 is output only for a predetermined time T. In this case, it is determined that one receiver has received the third signal, and the transmission of the transmission continuation command signal is not performed since the reception up to the preset second report has been completed.

  For this reason, the fire detector at address 5 stops the transmission of the common fire signal 33 when a certain time T has elapsed from time t5. Similarly, for the fire detectors that have detected a fire after the fourth report, a fire signal that is in common with the address signal is transmitted only for a fixed time T.

  For this reason, in a plurality of fire detectors connected to the same detector line, the number of fire detectors that transmit signals redundantly is limited to the third report, and the third report is limited to a certain time T. As shown in FIG. 4A, the sensor line voltage is reduced only by the voltage effect of the receiving resistor R2 corresponding to the alarm current generated by the signal transmission for the three fire detectors as shown in FIG. 4A. Even if fire detectors connected to the same sensor line 2 detect fires one after another, the detector line voltage is suppressed to a voltage drop of 3 reports, and the power supply voltage to the fire detector is greatly reduced to detect fire. And a situation in which communication with the receiver becomes impossible can be surely prevented.

  For the third and subsequent reports, if multiple fire detectors detect fire simultaneously, even if a common fire signal is transmitted with the address signal 32 over a certain time T, the detector line voltage temporarily increases during that time. Although it will decrease, in the actual fire occurrence situation, the fire detectors are installed at a certain distance, so it is basically not assumed that simultaneous alarms will be made in time. It is very unlikely that a fire detector will send a signal with simultaneous alerts.

  FIG. 6 is a flowchart showing the alarm control process by the fire detector of FIG. In FIG. 6, when a fire alarm is determined in step S1, the process proceeds to step S2 to transmit a fire signal common to the address signal. Subsequently, in step S3, it is determined whether a certain time has elapsed. When the certain time has elapsed, the process proceeds to step S4, and it is checked whether or not a common fire signal transmission continuation command is received from the receiver.

  For example, in the case of either the first report or the second report, step S5 is skipped because the transmission continuation command is received from the receiver. On the other hand, for the third and subsequent reports, since no transmission continuation command is received from the receiver, transmission of a common fire signal is stopped in step S5. Subsequently, in step S6, it is checked whether or not there is a fire recovery. If there is a fire recovery, an initialization process is performed in step S7, and then the process returns to step S1.

  FIG. 7 is a flowchart showing reception control processing by the receiver of FIG. In FIG. 7, in step S1, the signal state of the sensor line is sequentially read for each of the receiving circuit sections 6-1 to 6-n in FIG. 1, and when signal reception is determined in step S2, the process proceeds to step S3 and fire alarm processing is performed. Do. In this fire alarm process, for the first report, a representative fire display and a district display corresponding to the sensor line are performed. For the second and subsequent reports, the number of reports and the sensor address are displayed.

  Next, in step S4, it is checked whether or not the report is less than the third report. If it is less than the third report, that is, if it is the first report and the second report, the process proceeds to step S5. Send a fire signal transmission continuation command. On the other hand, if it is the third and subsequent reports, step S5 is skipped and the transmission continuation command is not transmitted.

  Next, in step S6, it is checked whether or not the fire is restored. The process from step S1 is repeated until the fire is restored. If there is a fire restoration, the restoration process is performed in step S7, and the process returns to step S1.

  FIG. 8 is an explanatory view showing a second embodiment of the present invention. Like the embodiment of FIG. 3, one of the sensor lines in FIG. 1 is extracted and shown.

  In FIG. 8, the sensor line 2 drawn from the receiver 1 has no. 1-No. A fire detector 3 having addresses 1 to n indicated by n is connected, and the fire detector 3 is shown as a switching circuit 14 in which an alarm control unit 18, a resistor R1, and a transistor Q1 are connected in series.

  As for the receiver 1, a receiving circuit section 6 is shown, which is connected from the power supply line of the power supply voltage + Vcc to the L side which is the plus side of the sensor line 2 via the reception resistor R2, thereby supplying the power supply voltage to the sensor line. Supply.

  In the second embodiment, the alert control unit 18 of the fire detector 3 detects the number of alerts on the sensor line 2 and fires until the alert count reaches a predetermined value, for example, the second alert. A common address signal is continuously transmitted following the address signal at the time of detection. From the third report that the number of reports reaches the second report, the address signal and the common fire signal are transmitted only for a fixed time T when a fire is detected. Send sequentially.

  In the receiver 1, based on the reception output of the receiving circuit unit 6, the reception control unit 12 of the MPU 5 shown in FIG. 1 receives the common fire signal transmitted from the fire detector 3 for each sensor line and gives an alarm. The sensor is identified from the address signal and displayed or controlled. Note that the MPU 5 provided in the receiving unit 1 of this embodiment has only the function of the reception control unit 12 and excludes the function of the command output unit 25.

  FIG. 9 is a time chart showing the signal transmission operation at the time of fire alarm in FIG. 8, taking as an example the case where fire detection is performed in the order of address 2, address 3, and address 5. 9A shows the sensor line voltage, and FIGS. 9B, 9C and 9D show ON / OFF of the transistor Q1 of the switching circuit 14 of the fire detector 3 at addresses 2, 3, and 5. ing.

  In FIG. 9, when the fire detector at address 2 detects a fire at time t1, the transistor Q1 of the switching circuit 14 is turned on and off, and the address signal 34 corresponding to address 2 is transmitted, and then the transistor Q1 is turned on. Operate to the state and send a common fire signal 35. Here, the fire detector at address 2 detects the first report by detecting its own fire, and continuously transmits a common fire signal 35 for the first report.

  Next, assuming that the fire detector at address 3 detects a fire at time t2, an address signal 36 indicating address 3 is transmitted by turning on and off the transistor Q1 of the switching circuit 14, and subsequently, by turning on the transistor Q1. A common fire signal 37 is output. The fire detector at address 3 detects the second report by detecting its own fire, and continues to transmit the common fire signal 37 because it is the second report.

  When the fire detector at address 5 detects a fire at time t3, an address signal 38 indicating address 5 is transmitted. The fire detector at address 5 detects the third report by its own fire detection, and for the third and subsequent reports, a common fire signal 39 is output following the address signal 38 for a fixed time T from time t3. To do.

  According to the fire alarm control of the embodiment of FIG. 8 as described above, as shown in the time t1-t3 of FIG. The voltage drops, but even if the number of alarms increases further, the detector line voltage does not decrease. As a result, the number of alarm fire detectors increases and the power supply voltage by the fire detector decreases. Fire detection can reliably prevent a situation in which communication with the receiver 1 is disabled. In addition, the history and number of fire detector reports can be grasped in detail.

  FIG. 10 is a flowchart showing the alarm control process by the fire detector of FIG. In FIG. 10, it is determined in step S1 whether or not it is a fire of its own. If it is not its own fire, the signal state of the sensor line is read in step S2, and a common signal from other fire detectors is read in step S3. Whether or not a fire signal has been transmitted is checked. If there is a transmission, the number of notifications is counted in step S4.

  If it is determined in step S1 that its own fire has been issued, an address signal is transmitted in step S5. Then, in step S6, whether or not the number of notifications obtained by adding its own notification to the previous number of notifications is the third report. If it is checked and it is the first or second report, the process of step S7 is skipped. If it is the third report or later, transmission of a common fire signal is stopped after a predetermined time in step S7.

  Subsequently, in step S8, it is checked whether or not there is a fire recovery. If fire recovery is determined, an initialization process is performed in step S9, and then the process returns to step S1.

  Note that the reception control process of the receiver 1 in the second embodiment of FIG. 8 is the same as the process excluding steps S4 and S5 in the flowchart of FIG. Also, in the first embodiment shown in the time chart of FIG. 4 and the second embodiment shown in the time chart of FIG. 9, a fire signal common to the address signal is transmitted for the signal transmission from the fire detector at the time of fire detection. However, in the first embodiment, when a transmission continuation command is received from the receiver, a common fire signal is continued after the address signal. In the second embodiment, a common fire signal may be continuously transmitted following the address signal following the first and second reports.

  In the above embodiment, the common fire signal is transmitted after the address signal is first transmitted at the time of fire detection. Conversely, the address signal is transmitted after the common fire signal is transmitted first. You may make it transmit.

  In the above embodiment, transmission of the third and subsequent reports is stopped. However, the present invention is not limited to this, and transmission of the fire detectors of the second and subsequent reports may be stopped. It may be set to any number that allows the system to reliably monitor fires.

The present invention includes appropriate modifications that do not impair the object and advantages thereof, and is not limited by the numerical values shown in the above embodiments.

Explanatory drawing of the fire alarm system to which the present invention is applied Explanatory drawing which showed embodiment of the fire detector of FIG. Explanatory drawing which took out one of the sensor lines of Drawing 1, and showed a 1st embodiment of the present invention. Time chart showing signal transmission operation at the time of fire alarm in FIG. Time chart showing the signal transmission operation at the time of fire alarm when the transmission continuation command is not output in FIG. The flowchart which showed the alarm control processing by the fire detector of FIG. The flowchart which showed the reception control processing by the receiver of FIG. Explanatory drawing which showed 2nd Embodiment of this invention. Time chart showing signal transmission operation at the time of fire alarm in FIG. The flowchart which showed the alarm control processing by the fire detector of FIG. Time chart showing common fire signal transmission operation in conventional systems

Explanation of symbols

1: Receiver 2, 2-1 to 2-m: Sensor line 3: Fire sensor 4: Termination resistor 5: MPU
6-1 to 6-m: reception circuit unit 7: operation unit 8: alarm display unit 9: district display unit 10: message output unit 11: memory 12: reception control unit 13: rectifier circuit / noise absorption circuit 14: switching Circuit 15: Constant voltage / current limiting circuit 16: Operation indicator lamp 17: Address setting circuit 18: Alarm control unit 19: Oscillating circuit 20: Light emitting element 21: Light receiving element 22: Amplifier circuit 23: Comparison circuits 24, 24-1 -24-m: Command output circuit 25: Command output unit 26, 29, 32, 34, 36, 38: Address signal 27, 30, 33, 35, 37: Common fire signal 28, 31: Transmission continuation command signal

Claims (4)

In a fire alarm system in which a plurality of fire detectors are connected to a sensor line drawn from a receiver,
The fire detector transmits an address signal and a common fire signal only for a certain period of time when a fire is detected and issued, and when the transmission continuation command is received from the receiver, after the lapse of the certain period of time Is equipped with an alarm control unit that continues to transmit a common fire signal,
The receiver
A reception control unit that receives and alerts a common fire signal transmitted from the fire sensor in units of sensor lines and identifies the sensor from an address signal;
Command output for outputting a transmission continuation command to the sensor line to designate a fire sensor address for which the detection is detected and continue transmission of a common fire signal until the number of detection detections for the same sensor line reaches a predetermined number And
A fire alarm system characterized by comprising:
2. The fire alarm system according to claim 1, wherein when the command output unit of the receiver receives a common fire signal received from the same sensor line, it designates the first sensor address and outputs one report. A fire alarm system for outputting a transmission continuation command for continuing transmission of a common fire signal only from an eye fire sensor to the sensor line.
In a fire alarm system in which a plurality of fire detectors are connected to a sensor line drawn from a receiver,
The fire sensor detects the number of fire alarms of other fire sensors in the same sensor line, and continues the address signal and the common fire signal at the time of fire detection until the number of alarm detections reaches a predetermined number. After the transmission detection number reaches a predetermined number, it has a notification control unit that transmits an address signal and a common fire signal only for a certain time when a fire is detected,
The receiver includes a reception control unit that receives and alerts a common fire signal transmitted from the fire detector in units of sensor lines and identifies the detector from an address signal. system.
  4. The fire alarm system according to claim 3, wherein the alarm control unit of the fire detector, when the alarm detection of the same sensor line is the second or later, is an address signal only for a certain time when the fire is detected. And a fire alarm system characterized by transmitting a common fire signal.

Images