JP2005122496A - Fire alarm facilities and fire sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the current consumption of the whole system when an automatic test of a fire sensor is conducted. <P>SOLUTION: In fire alarm facilities in which a plurality of fire sensors with an automatic test function are connected to signal lines led out of a fire receiver and fire signals from fire sensors are received by the signal lines, each fire sensor receives an operation stop command through the signal line to enter a sleep mode and then returns to its normal state after a specified time from the time when the operation stop command is received, and the test is conducted when the frequency of reception of the operation stop command matches its address. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fire alarm system for connecting a plurality of fire detectors having an automatic test function to a signal line led out from a fire receiver and receiving a fire signal from the fire detector in units of signal lines.

Automatic testing of fire detectors in a fire alarm system that connects multiple fire detectors equipped with an automatic test function to the signal line drawn from the fire receiver and receives fire signals from the fire detector for each signal line With regard to the above, there is a type in which a fire receiver transmits a test start signal for each signal line so that all fire detectors connected to the signal line perform an automatic test. (For example, refer to Patent Document 1).
JP 2001-184571 A

  However, since the fire receiver sends a test start signal for each signal line, all fire detectors connected to that signal line perform automatic tests. During this period, all fire detectors In the operating state, the current consumption of the entire system increases, and therefore the voltage of the signal line becomes unstable, and the fire receiver cannot accurately determine the pulse signal from the fire detector during this period. As a result, the fire may be misjudged.

  The present invention has been made to solve the above-described problems. A plurality of fire detectors having an automatic test function are connected to a signal line drawn from a fire receiver, and the signal from the fire detector is connected in units of signal lines. Regarding fire alarm equipment that receives fire signals, reduce the current consumption of the entire system during the automatic test of the fire detector, thus stabilizing the voltage of the signal line, the pulse signal from the fire detector during this period, etc. The purpose is to make it possible for the fire receiver to accurately determine the above.

  The present invention provides a fire alarm system for connecting a plurality of fire detectors having an automatic test function to a signal line drawn from a fire receiver and receiving a fire signal from the fire detector for each signal line. A receiver configured to detect a disconnection of the signal line in accordance with a voltage level of the signal line; and a transmission / reception for transmitting a signal between the plurality of fire detectors via the signal line; An operation stop command for setting each of the fire detectors to a sleep mode via the signal line, and when a predetermined time elapses after the operation stop command is output, Control means for discriminating disconnection of the signal line, and each of the fire detectors enters a sleep mode upon receiving the operation stop command via the signal line, and the operation stop control When a predetermined time period from the reception of the command has elapsed, returns to the normal state, also, the number of times that has received the operation stop command when a match with the own address, and performing the tests.

  In addition, the fire receiver outputs a test result return command for collecting test results of the automatic test function in each fire detector via the signal line, and each fire detector receives the signal line via the signal line. The test result is output by receiving the test result return command.

  Each of the fire detectors is a flame detector having a sensitivity test function of a fire detection unit and a contamination degree measurement test function of a light receiving window as the automatic test function.

  The present invention also provides a fire detector connected to a signal line drawn from a fire receiver and outputting a fire signal by a switching operation, and having an automatic test function, and the fire receiver via the signal line. Receives the operation stop command sent to detect the disconnection of the signal line, thereby entering the sleep mode and returning to the normal state when a predetermined time elapses after receiving the operation stop command. In addition, the test is performed when the number of times the operation stop command is received coincides with its own address.

  According to the first aspect of the present invention, a fire in which a plurality of fire detectors having an automatic test function are connected to a signal line drawn from a fire receiver, and a fire signal from the fire detector is received for each signal line. In the notification facility, each fire detector can perform an automatic test using an operation stop command sent by the fire receiver as a trigger to determine the disconnection of the signal line. In addition, since only one fire detector in which the number of times that the operation stop command has been received matches the address of each fire detector is automatically tested, the current consumption of the entire system during the fire detector automatic test is performed. Therefore, the voltage of the signal line is stabilized, and the pulse signal from the fire detector during this period can be accurately determined on the fire receiver side. That is, since the current consumption of the entire signal line during the automatic test can be suppressed, there is almost no voltage drop of the signal line during the automatic test, and the fire detection circuit of the fire receiver does not detect it as a fire signal.

  According to invention of Claim 2, a fire receiver outputs the test result return command which collects the test result of the automatic test function in each fire detector, and each fire detector receives a test result return command. Thus, since the test result is output, the fire receiver can reliably receive the test result of each fire detector.

  According to a third aspect of the present invention, each fire detector is a flame detector provided with a sensitivity test function for a fire detector and a test function for measuring the degree of contamination of a light receiving window as automatic test functions. For this reason, the current consumption of the circuit constituting the automatic test function is larger than that of a sensor other than a flame sensor such as a photoelectric smoke sensor or a thermistor heat sensor. For this reason, only one fire detector whose number of times that the operation stop command is received matches the address of its own among the fire detectors connected to the signal line performs the automatic test. The current consumption of the entire system during the execution of the automatic test is reduced, so that the voltage of the signal line is stabilized, and the pulse signal from the fire detector during this period can be accurately determined on the fire receiver side. That is, since the current consumption of the entire signal line during the automatic test can be suppressed, the fire detection circuit of the fire receiver does not detect a voltage drop of the signal line during the automatic test as a fire signal.

  According to the fourth aspect of the present invention, the fire detector is connected to the signal line drawn from the fire receiver, outputs a fire signal by switching operation, and has an automatic test function. An automatic test can be performed with the operation stop command sent by the fire receiver as a trigger to determine the disconnection of the line. Therefore, the fire detector can receive a fire signal due to a switching operation, and a fire alarm device (so-called P-ATF type system) connected to a fire receiver that performs signal transmission, can not transmit a signal but fire due to a switching operation Any fire alarm equipment (so-called P-type system) connected to a fire receiver capable of receiving signals can be configured. In other words, it is not necessary to set the execution of the automatic test function according to the system so that an automatic test is performed in the P-ATF type system and an automatic test is not performed in the P type system. In addition, since the sensor itself does not always perform an automatic test, current consumption during normal operation can be suppressed.

  In addition, since the automatic test is performed when the number of times the sleep mode start command is received matches the address of its own, the current consumption of the entire system during the automatic test of the fire detector is reduced, and therefore the voltage of the signal line is reduced. In this period, the pulse signal from the fire detector during this period can be accurately determined on the fire receiver side. That is, since the current consumption of the entire signal line during the automatic test can be suppressed, the voltage detection of the signal line during the automatic test is detected as a fire signal by the fire detection circuit of the fire receiver of the P-ATF type system. There is nothing.

  FIG. 1 is a diagram showing a P-type system PS1 according to an embodiment of the present invention, and FIGS. 2 and 3 are block diagrams of a fire receiver RE1 and a fire detector SE1.

  In the P-type system PS1 shown in FIG. 1, a plurality of fire detectors SE are connected to one fire receiver RE.

  Each fire detector SE is supplied with power from the fire receiver RE, and measures physical quantities such as smoke concentration and infrared rays radiated from the flame, thereby monitoring the fire.

  In FIG. 2, a fire receiver RE1 is used as the fire receiver RE of FIG. 1, and includes a power supply unit 11, a signal transmission circuit 12, a signal reception circuit 13, a fire detection circuit 14, and a disconnection detection circuit 15. A control circuit 16, a main control unit 17, and a display operation unit 18, a common terminal C to which a power and signal line is connected, and a plurality of line terminals L 1 to Ln, and a plurality of fire detectors SE. Is provided. Each line is configured between these terminals C and L1 to Ln, and a terminator is arranged at each terminal portion. Of the block configuration in the fire receiver RE1, a signal transmission circuit 12, a signal reception circuit 13, a fire detection circuit 14, a disconnection detection circuit 15, and a control circuit 16 are arranged for each line. It arrange | positions for every terminal L1-n.

  The fire detector SE1 has an automatic test function and is used as the fire detector SE of FIG. 1 or FIG. 2, and includes a light emitting circuit 31a1, a fire detector 31a2, an amplifier circuit 31b, A light emitting circuit 32a1, a fouling detector 32a2, an amplifier circuit 32b, a light receiving window 33, a band pass filter 34, a transmission transmitting circuit 41, a transmission receiving circuit 42, a constant voltage circuit 51, a time measuring circuit 61, A microcomputer 71 as a control circuit, a confirmation lamp circuit 80, a clock oscillation circuit 81, an EEPROM 91 in which addresses and the like are stored, and a diode bridge DB are included.

  FIG. 4 is a circuit diagram showing the transmission transmission circuit 41 of the fire detector SE1 of FIG.

  The transmission / transmission circuit 41 includes transistors Qy1 and Qy2, a Zener diode Zy, and a recovery detection circuit 50. The recovery detection circuit 50 includes a transistor Qz and a diode Dz.

  When the fire detector SE1 transmits a fire output signal, the corresponding port of the microcomputer 71 is maintained at the Hi level. Since this Hi level is supplied to the base of the NPN transistor Qy1, the transistor Qy1 becomes conductive, and the transistor Qy2 becomes conductive through the Zener diode Zy. If the output of the microcomputer port can maintain the Hi level as it is, the power / signal output terminals C and L of the fire detector SE1 are substantially short-circuited to a low impedance state via the diode bridge DB. Here, the Hi level is a voltage higher than the reference level with respect to the input to the port of the microcomputer 71, and the Lo level is a reverse low voltage, specifically no voltage or 0V. The same applies to Hi output and Lo output.

  In this state, since the collector of the transistor Qy1 is conductive to the ground GND, the emitter side of the transistor Qz is connected to the ground GND, and the output voltage of the constant voltage circuit 51 is + Vcc via the diode Dz. Since the transistor Qz connected to is also in a conductive state, the anode side of the diode Dz becomes a low potential, and the Lo voltage is sent to the fire signal input to the microcomputer 71. As long as the voltage is supplied from the fire receiver RE in this way, this state continues and the fire output state is maintained.

  Here, when the recovery button of the fire receiver RE is pressed, the power supply from the fire receiver RE to the fire detector SE1 is cut off for about 1 second. That is, the power supply between the power / output terminals C and L is stopped. For this reason, since the base current to the transistor Qz is also interrupted, the transistor Qz is cut off, the diode Dz is also cut off, and its anode potential rises to the same voltage as the + Vcc voltage supplied through the resistor. Then, the Hi voltage is sent to the fire signal input to the microcomputer 71. In other words, when the microcomputer 71 outputs a fire signal, the input from the recovery detection circuit 50 becomes + Vcc voltage, so that the microcomputer 71 can reliably catch the recovery signal. The + Vcc supply source is a capacitor provided in the constant voltage circuit 51 (not shown in detail), and is provided so that the microcomputer 71 can operate even when the power supply is cut off at the time of the restoration signal. The input from + Vcc to the port of the microcomputer 71 is a small current consumption and does not affect the power supply when the microcomputer 71 is restored.

  During normal monitoring, the transistors Qy 1, Qy 2, and Qz are also cut off, so that no current based on the power / output terminals C and L flows through the recovery detection circuit 50. As a result, the current consumption for monitoring the restoration signal of the fire detector SE1 during monitoring is reduced, and the number of installed units can be increased.

  Further, the recovery detection circuit 50 stops the Hi input to a predetermined port of the microcomputer 71 powered by + Vcc by turning on the transistor Qz based on the turning on of the transistor Qy1 during the switching operation of the transmission / transmission circuit 41. As the power and output terminals C and L are interrupted by a signal, Hi input is performed to a predetermined port of the microcomputer 71. However, the input to the predetermined port for detecting the recovery signal in the microcomputer 71 is as follows. It may be based on the voltage between the power / output terminals C and L. That is, when the transistor Qy1 is turned on by the switching output from the microcomputer 71, a line connecting the portion where the remaining voltage based on the Zener diode Zy is generated to the collector of the transistor Qy1 is formed, and the microcomputer 71 uses the predetermined voltage from the line. Hi input can be performed to a predetermined port. In this case, the input to the predetermined port of the microcomputer 71 becomes Hi input during the switching operation from the normal state, and based on the power cutoff between the power / output terminals C and L by the recovery signal, the input to the predetermined port of the microcomputer 71 is performed. The input becomes Lo input, and the microcomputer 71 can detect the recovery signal by the change of the input. Also in this case, monitoring of the recovery signal is not required at all times, so that no current consumption is generated, and the input to the predetermined port of the microcomputer 71 is performed only during the switching operation of the transmission / transmission circuit 41. can do.

  FIG. 5 is a circuit diagram showing the transmission receiving circuit 42 in the fire detector SE1 of FIG.

  In contrast to the conventional example, the transmission / reception circuit 42 shown in FIG. 5 has a small current when the voltage between the power / signal output terminals C and L is higher than the threshold, and the power / signal output terminals C and L In this circuit, the current increases when the voltage between them is lower than the threshold value.

  In the circuit shown in FIG. 5, the threshold is determined by the Zener voltage of the Zener diode Zx and the resistance values of the resistors Rx1 and Rx2. The transistor Qx is a MOS-FET, and when the gate-source voltage becomes equal to or higher than a certain voltage (ON voltage), the source-drain is made conductive.

  That is, the voltage value divided by the resistors Rx1 and Rx2 is obtained by subtracting the voltage drop of the diode bridge DB and the Zener voltage of the Zener diode Zx from the voltage applied between the power supply / signal output terminals C and L of the fire detector SE1. When the ON-voltage of the transistor Qx and the forward voltage of the diode Dx are subtracted from the + Vcc voltage, and the source-gate voltage of the transistor Qx becomes equal to or higher than the ON voltage, the source-drain of the transistor Qx becomes conductive. Since the + Vcc voltage is applied to the resistor Rx4, the Hi voltage is input to the microcomputer 71.

  Therefore, a state in which the voltage applied between the power / signal output terminals C and L is high (that is, a normal monitoring state) surely turns off the transistor Qx. The transistor Qx, the Zener diode Zx, and the resistors Rx1 and Rx2 may be selected so that the transistor Qx becomes conductive at a voltage equal to or lower than the voltage to be set.

  Although a Pch MOS-FET is used as the transistor Qx, a PNP transistor may be used.

  According to the above embodiment, when the input voltage of the voltage detection circuit of the transmission / reception circuit is high, the current consumption of the determination circuit is low, and when the input voltage is low, the current consumption of the determination circuit increases. The current consumption of the fire detector SE1 is small.

  FIG. 6 is a circuit diagram showing a specific example of the confirmation lamp circuit 80 in the fire detector SE1 of FIG.

  The confirmation lamp circuit 80 shown in FIG. 6 is an emitter follower circuit. In a conventional fire detector, there is an example in which an emitter follower circuit is used as a confirmation lamp circuit. The voltage applied to the fire detector is nominally 24V, but actually varies from 17-30V. In order to obtain a constant brightness with respect to a varying voltage, an emitter follower circuit capable of obtaining a constant current is advantageous.

  The confirmation lamp circuit 80 shown in FIG. 6 has a point that a base resistor R1 that is originally unnecessary in the emitter follower circuit is inserted, and a point that guides a signal between the base resistor R1 and the base to the voltage discriminating means. There is a feature.

  As a result, in the unlikely event that the confirmation lamp LA runs out of bulb, no current is supplied to the collector, so the base current increases and the voltage drop due to the base resistance R1 increases. Therefore, if the voltage determination means determines the voltage at the connection point between the resistor R1 and the base, it is possible to find out that the confirmation lamp LA has run out.

  Next, the operation of the confirmation lamp circuit 80 will be specifically described using numerical values.

  In the confirmation lamp circuit 80 shown in FIG. 6, the current amplification factor of the transistor Q1 is set to 100, the base-emitter voltage VBE is set to 0.6 V, and the current required for lighting the confirmation lamp LA is set to 3.0 mA. Is 3.0 V, the value of the resistor R2 is as follows.

  R2 = (3.0V−0.6V) /3.0 mA = 800Ω The value of the resistor R1 is 1 kΩ for convenience.

  Here, when the confirmation lamp LA is normal, a current flows to the collector of the transistor Q1 via the confirmation lamp LA. In this case, since the base current is a fraction of the current amplification factor of the emitter current, 3 mA ÷ 100 = 30 μA. Therefore, the voltage at the connection point between the resistor R1 and the base (voltage guided to the voltage determining means) is 3.0V-1 kΩ × 30 μA = 2.97V.

  On the other hand, when the check lamp LA is broken, no current is supplied to the collector of the transistor Q1. Therefore, the voltage at the connection point between the resistor R1 and the base (voltage guided to the voltage determining means) is obtained by subtracting the base-emitter voltage VBE of the transistor Q1 from the voltage of the lighting signal, and the resistance between the resistors R1 and R2. Since it is a value obtained by adding the base-emitter voltage VBE to the one divided by the ratio, (3.0V−0.6V) × {800Ω / (1 kΩ + 800Ω)} + 0.6V = 1.67V.

  Therefore, it is possible to recognize whether or not the check lamp LA has run out based on the voltage guided to the voltage determination means.

  The voltage discrimination means may use the A / D conversion function of the microcomputer 71, a discrimination circuit using a Zener diode, a transistor, etc., a circuit using an operational amplifier, etc. Also good.

  Thereafter, the fire detector SE1 in which a ball break is detected in response to an inquiry from the fire receiver RE returns an abnormal signal, so the fire receiver RE does not miss the ball break of the fire detector SE1.

  Next, the fire detection operation and the automatic test function of the fire sensor SE1 of FIG. 3, that is, the flame sensor having the automatic test function will be described.

  In the fire detector SE1, as a fire detection operation, the pyroelectric element as an example of the fire detection unit 31a2 always receives infrared rays emitted from the flame via the light receiving window 33 and the band pass filter 34, and an amplification circuit. Amplified at 31 b, the output level is input to the microcomputer 71, and if it is equal to or higher than the fire determination level stored in the EEPROM 91, it is determined that a fire has occurred.

  In addition, the fire detector SE1 has two automatic test functions: a fire detection unit sensitivity test function and a light receiving window contamination degree measurement test function.

  The fire detection unit sensitivity measurement test function inputs the output level when the fire detection unit 31a2 receives light reflected from the light emission circuit 31a1 and reflected by the bandpass filter 34 to the microcomputer 71. If the output level is outside the normal level range stored in the EEPROM 91, it is determined that the fire detection unit is abnormal, and this normal level is, for example, a range of 70% or less and 150% or more of the initial output level. .

  The light receiving window contamination degree measurement test function inputs the output level when the light emitting circuit 32a1 emits light and the light emission is received by the contamination detecting unit 32a2 through the light receiving window 33 to the microcomputer 71, and the output level is input to the EEPROM 91. If it is below the stored contamination level limit level, it is determined that the light receiving window has been contaminated. This contamination level limit level is, for example, 70% or less of the initial output level.

  Such an automatic test operation in the fire detector SE1 is performed when the number of times of receiving the operation stop command sent from the fire receiver RE1 coincides with its own address.

  The fire detector performs an automatic test at such a predetermined interval to detect its own abnormality, and transmits an information collection signal (test result return command) based on the transmission signal from the fire receiver RE. When receiving via the reception circuit 42, a response signal based on the transmission signal can be sent via the transmission transmission circuit 41 as normal or abnormal.

  In such a P-type system PS1, as a result of fire monitoring, when the physical quantity increases to a level that requires an alarm, the fire detector SE supplies its own power line (transmission line) to the fire receiver RE. By short-circuiting, so-called switching operation, the line current is increased and a fire is notified.

  In addition, if it is not a fire, it may be determined whether or not the automatic test result is appropriate, and the determination result may be transmitted in response to an inquiry from the fire receiver RE.

  Here, the fire detector SE sends information to the fire receiver RE by changing the line voltage. Such an inquiry from the fire receiver RE and a response from the fire detector SE are performed by a serial transmission method.

  Here, when serial transmission is performed, an accurate time reference is required not only on the fire receiver RE side but also on the fire detector SE side. For example, when predetermined information is transmitted from the fire receiver RE to the fire detector SE, two pulses are transmitted, and desired information is transmitted based on the interval between the two pulses transmitted. The reference pulse may be one pulse width instead of the interval between two pulses.

  FIG. 7 is a diagram illustrating an example of codes transmitted from the fire receiver RE to the fire detector SE1 in the P-type system PS1.

  In the case of sending information to the fire detector SE1 by the signal transmission circuit 12 in FIG. 2, the fire receiver RE1 has a pulse voltage of 7V and a pulse width of the line supplying the power supply voltage 24V to the fire detector SE1. A command in which two pulses of 2 ms are superimposed and the interval between these two pulses is 4 ms is a command representing the code 00b shown in FIG.

  A command with a pulse interval of 6 ms is a command representing the code 01b shown in FIG.

  As schematically shown in FIG. 7, the microcomputer 71 on the fire detector SE detects the arrival of two pulses by the signal receiving circuit 42 in FIG. 3 at the interval of two pulses arriving in the line voltage. The circuit 81 counts the number of rising clock pulses generated by itself, and determines the interval between the two pulses based on the counted number.

  That is, in the case shown in FIG. 7 (1), the interval between the two pulses received from the fire receiver RE is 4 ms, and the clock pulse generated by the fire detector SE during the two pulse intervals of 4 ms. Count the number of rises. In the case shown in FIG. 7 (2), the interval between the two pulses received from the fire receiver RE is 6 ms, and the clock pulse generated by the fire detector SE during the two pulse intervals of 6 ms. Count the number of rises.

  If the clock pulse frequency generated by the fire detector SE has an error of + 20%, the rise of the clock pulse generated by the fire detector SE is shown in FIG. 7 (1) at a pulse interval of 4 ms. In the pulse interval of 6 ms, as shown in FIG. 7 (2), the rising edge of the clock pulse generated by the fire detector SE is counted six.

  Therefore, when there is an error of + 20% in the clock pulse frequency generated by the fire detector SE, if the rising number of clock pulses generated by the fire detector SE is 4, it is determined that the interval between the two pulses is 4 ms. If the number of rising clock pulses generated by the fire detector SE is 6, it can be determined that the interval between the two pulses is 6 ms. Actually, the clock pulse is quite fast, and is close to a proportional value of 1.5 times or 2 times.

  If the error of the clock pulse frequency generated by the fire detector SE is 0%, if the rising number of clock pulses generated by the fire detector SE is 3, it is determined that the interval between the two pulses is 4 ms. If the number of rising edges of the clock pulse generated by the fire detector SE is 4, it can be determined that the interval between the two pulses is 6 ms.

  Further, when the error of the clock pulse frequency generated by the fire detector SE is −20%, if the rising number of clock pulses generated by the fire detector SE is 3, the interval between the two pulses is 4 ms. If the number of rising edges of the clock pulse generated by the fire detector SE is 4, it can be determined that the interval between the two pulses is 6 ms.

  In each of the above cases, when the clock pulse frequency error changes, the number of counted pulses is different even at the same time interval, but if the clock pulse frequency error is the same, the relationship between the time interval and the counted pulse number is: The same. That is, if the clock pulse frequency error is the same, the two pulse intervals can be accurately determined based on the counted number of pulses.

  That is, the reason why the frequency variation in the clock pulse oscillation circuit configured inexpensively without using elements such as crystal and ceramic is as large as ± 20% to 200% is as follows: (1) Variation in characteristics of individual elements; 2) Environmental changes such as ambient temperature are the main factors. Therefore, although the characteristics of each individual element vary depending on the ambient temperature and the like, it can be considered that the ambient temperature and the like are constant within a short span of several seconds.

  Therefore, when the same fire detector SE has two pulse intervals and the number of rising edges of the clock pulse is 4, when the clock pulse frequency error is + 20%, the two pulse intervals are 4 ms and the code 00b is recognized. In the state where the error is −20%, the interval between two pulses is 6 ms, and can be recognized as the code 01b.

  FIG. 8 is a diagram showing a code based on the reference pulse and the pulse interval sent from the fire receiver RE based on the explanation of FIG.

  As in the case of FIG. 7, the fire receiver RE first sends a reference pulse of 4 ms interval to the fire detector SE, and then sends a pulse of 4 ms interval as a code to the fire detector SE. To do.

  By doing the above, even if the clock pulse frequency is shifted by ± 20%, if the number of rising edges of the clock pulse within the reference pulse interval (4 ms) is compared with the number of rising edges within the pulse interval thereafter, Since they are the same, the fire detector SE can accurately capture the code from the fire receiver RE.

  FIG. 9 is a diagram illustrating the reference pulse and the pulse transmitted at a different interval from FIG. 8 by the fire receiver RE, as in FIG.

  In the example shown in FIG. 9, the fire receiver RE first sends a reference pulse of 4 ms interval to the fire detector SE, and then sends a pulse of 6 ms interval as a test return command to the fire detector SE. To send.

  By doing the above, even if the clock pulse frequency is shifted by ± 20%, the number of rising edges of the clock pulse within the reference pulse interval (4 ms) is compared with the number of rising edges within the subsequent pulse interval (6 ms). Then, the fire detector SE can accurately capture the test return command from the fire receiver RE. That is, since the number of rising edges of the subsequent pulse interval has changed to about 1.5 times, the fire detector SE can accurately recognize that the code is 01b. Similarly, even if the pulse interval representing the code becomes long, such as 8 ms, it can be accurately determined.

  The above explanation is an example of the fire receiver RE and the fire detector SE that are fire alarm equipments. However, the configuration of the central control device that is the fire receiver RE and the fire detector SE (that is, the terminal) connected thereto is described. Therefore, the above embodiment can be applied, and thus the hardware configuration of the terminal can be reduced, and accurate information transmission can be achieved.

  Note that the longer the width of the reference pulse with respect to the clock frequency, the higher the accuracy, that is, the greater the number of rising edges of the clock frequency in the reference pulse, the less misunderstanding of the code and the more accurate transmission.

  According to the above, the fire receiver outputs a reference pulse indicating a predetermined time width, and by responding to each fire detector in accordance with this, the clock pulse in the microcomputer of each fire detector varies greatly. However, it can be adjusted to the fire receiver, and the time width can be standardized.

  Further, according to the above embodiment, since the reference pulse is included in the configuration of the polling output signal, each fire detector SE can adjust the timing every time it receives the polling output signal, and stores the timing. There is no need to do.

  Furthermore, according to the above embodiment, when the response signal code is represented by a time width, the time width is unified, so that reliable signal transmission can be performed.

  Next, the above embodiment will be described more specifically.

  FIG. 10 is a diagram illustrating an example of polling transmission in the above embodiment.

  In FIG. 10, “parent” is the fire receiver RE in FIG. 1, and “child” is the fire detector SE.

  In the case of polling transmission in the above embodiment, the fire receiver RE is assigned a plurality of individual fire detectors SE for each line, and groups the fire detectors SE based on the addresses, Data for the fire detector SE is collected in units of 15 addresses, and a start pulse, a reference pulse, and CM1 are transmitted.

  The activation pulse is an activation pulse for activating the microcomputer 71 of the fire detector SE, and the fire receiver RE transmits a Lo pulse having a pulse width of 2 ms. The fire detector SE returns the microcomputer 71 from the sleep mode and prepares for reception of the reference pulse. Note that the microcomputer 71 enters the sleep mode after a necessary operation such as a fire detection operation, and requires a stable time after starting from this state.

  The reference pulse is a reference pulse that is a basic length of a transmission pulse interval, and is 4 ms at a falling edge interval (H → L to H → L).

  CM1 is a control command to the fire detector SE, and an 8-bit code is indicated by four pulse intervals, and for each pulse interval, as shown in FIG. 8, each pulse interval is judged and replaced with a code. .

  As shown in FIG. 11, a 2-bit code is indicated by a falling edge interval (tb). For example, the control command CM1 shown in FIG. 12 is 10110101b = B5h. The code contents of the control command CM1 are as shown in FIG. In other words, 5 bits from b7 to b3, here, a line is designated by 10110b, 2 bits from b2 and b1, here, 10 is used to instruct a control command and selecting of the fire detector SE, and an odd parity of b0 Is added. The fire detector SE makes no response when it detects a parity error.

  Then, when waiting for transmission, the fire detector SE analyzes the control command CM1.

  Slots 0 to 14 determine the timing of transmission from the fire detector SE to the fire receiver RE, and are defined as shown in FIG. 13 by the polling 1or2 and the slot position based on its own address.

  The fire detector SE transmits the pulse shown in FIG. 13 to the specified slot.

  The pulse from the fire detector SE is output by the microcomputer 71 via the transmission / transmission circuit 41 in FIG. 3, and the code from the fire detector SE is represented by the pulse width. In FIG. The result when returning the automatic test result of SE is shown. That is, if the sensor is normal as a result of the automatic test, one pulse is returned with a pulse width of 2 ms. If it is abnormal, one pulse is returned with a pulse width of 4 ms.

  In selecting transmission, the data of the fire detector SE is collected for each address, and as shown in FIG. 14, the start pulse, the reference pulse, CM1 and CM2 are added to the transmission standby, and the receiver RE detects fire. To the SE.

  The start pulse, reference pulse, and CM1 are as described above, CM2 is an 8-bit control code similar to CM1, and the code transmission / reception method is the same as CM1. The control contents are represented by the contents of CM1 and CM2.

  Using such signal transmission, the fire receiver RE includes the control content of polling 1 or polling 2 in the control command CM1 and transmits it, so that the fire connected between the power / transmission lines C and L1 to Ln is transmitted. Information on the sensors SE can be collected, in which the fire receiver RE is collecting automatic test results from each fire sensor SE. In this embodiment, as shown in FIG. 2, since the signal transmission circuit 12 and the signal reception circuit 13 are provided for each of the power / signal lines C and L1 to Ln, the fire detector for each line. The signal is exchanged with the SE, and therefore the line designation portion in the control command CM1 may be ignored. This means that there are up to 30 addressed fire detectors SE with an automatic test function connected to one line.

  In this way, in the P-type system PS1, the fire signal from each fire detector SE is detected by the fire detector RE for each line by the fire detector RE, and the necessary signal transmission circuit 12 from the fire detector SE and The automatic test results can be collected by the signal receiving circuit 13, and the fire receiver RE can recognize that there is an abnormal fire sensor SE.

  [Detection of disconnection by setting fire detector in sleep mode] Next, termination detection processing in the above embodiment will be described.

  FIG. 15 is a time chart showing from the start pulse generation to the end of the end detection process in the above embodiment.

  The fire receiver RE sends an operation stop command (sleep mode start command) when performing end detection processing. When the fire detector SE receives the operation stop command shown in FIG. 12, the fire detector SE sets the microcomputer in the sleep mode and enters the minimum current consumption state.

  That is, the sleep mode is a mode in which the main circuit of the microcomputer is stopped and only the part that communicates with the outside is operated. Therefore, when all the fire detectors SE are in the sleep mode, the current consumption of the entire system is reduced, so that the voltage of the signal line is stabilized and the disconnection can be accurately detected.

  When the microcomputer 71 enters the sleep mode, the fire receiver RE checks whether or not a specified current is flowing in the line by the disconnection detection circuit 15. The fire detector SE activates an internal timer circuit when shifting to the sleep mode. The fire detector SE returns from the sleep mode after a specified time (about 100 ms) by the timer circuit and enters a normal monitoring state.

  In FIG. 15, the start pulse, the reference pulse, and CM1 are the same as in FIG. 10, and are 8-bit control codes. In preparation for operation stop, the fire detector SE confirms the code 11b as a control command. To enter sleep mode.

  When the operation is stopped, the fire detector SE sets the microcomputer 71 in the sleep mode, and the fire receiver RE performs a disconnection detection operation by the disconnection detection circuit 15 here.

  At the end of the end detection process, the fire detector SE returns from the sleep mode by an external interrupt from the internal timer circuit.

  The conventional fire receiver RE detects the disconnection by examining the presence or absence of a voltage in a normal state (so-called monitoring voltage) for the presence or absence of disconnection of the signal line to which each fire detector SE is connected. Here, in addition to the P signal as the fire signal, if the signal as the inspection result of the disconnection is transmitted, the voltage of the signal line fluctuates, so that the voltage when the disconnection is detected is reduced. There is a problem that it may be erroneously determined that the wire is disconnected.

  The above-described embodiment is intended to provide a fire alarm facility capable of monitoring disconnection by voltage in a state where the voltage state of the signal line is stable.

  In the above-described embodiment, for example, in a fire alarm facility using a P-type fire receiver RE, a fire detector having a so-called automatic test function is used. When collecting the signal line, the state of the signal line is stabilized and the disconnection of the signal line is detected.

  According to the above embodiment, the fire detectors controlled by the microcomputer change the state of the signal line depending on the current consumption, but the microcomputers of the fire detectors are simultaneously set to the sleep mode by the signal from the fire receiver. Therefore, it is possible to reliably detect disconnection.

  In addition, according to the above embodiment, the fire detector SE that has entered the sleep mode may be returned to the normal operation by providing a recovery signal. However, since it automatically returns over time, the fire detector SE is left in the sleep mode. Can be prevented.

  Furthermore, according to the above-described embodiment, the current consumption of the fire detector SE is large for a moment of the sampling operation and is stable at other times. If the microcomputer 71 enters the sleep mode after the sampling operation, the sampling operation timing is made very short, so that it is difficult to think that it overlaps in reality. Is in sleep mode. Therefore, reliable disconnection detection operation is possible. As the operation of the microcomputer 71 of the fire detector SE, the sleep mode is entered immediately after the sampling operation, and the operation is started by the own clock circuit 61, so that the sleep mode can be almost achieved. Although it is necessary to operate also with a transmission signal from the fire receiver RE, the fire receiver RE can stop transmission of the transmission signal during the disconnection detection operation.

  [ATF system in P-type fire receiver] In the above embodiment, a fire detector having a so-called automatic test function is used in a fire alarm facility using a so-called P-type fire receiver RE. The test results are collected from each fire detector.

  A P-type system with an R-type fire detector (a fire detector that has an automatic test function and an address and transmits to the fire receiver RE1) is not R-type because the entire system is not R-type. It is not necessary to use a refractory wire as a power / signal line for connecting the machine RE1 and the fire detectors SE, SE1. Therefore, when a fire detector having an R-type function is attached to the P-type system, there is an advantage that it is not necessary to replace the power / signal line.

  In addition, when attaching a fire detector having an R-type function to a P-type system, fire detection is performed in the P-type (the voltage drops when a fire is detected), and the fire detector inspection is changed to the R-type. This is convenient when checking where it is difficult for a person to check.

  Further, in the above embodiment, the main control unit 17 controls the timing of the operation of collecting the test results by signal transmission between the lines C and L1 to Ln in each control circuit 16. That is, if signal transmission from a plurality of fire detectors to the fire receiver is not performed simultaneously, the stability of the voltage in the power / signal line is not hindered.

  That is, according to the above embodiment, in the P-type fire alarm facility, the fire receiver RE and each fire detector are provided with a signal transmission function, respectively, and the fire signal is output by the impedance change between the signal lines. The fire receiver RE collects the automatic test results of each fire detector by signal transmission (R signal), so that a fire signal is sent out by switching operation. In the system, the number of fire detectors SE that have an inspection function can be used as many times as necessary. The transmission / reception circuit in the fire receiver RE collects inspection results by signal transmission separately from the fire signal. can do.

  In addition, according to the above-described embodiment, the plurality of transmission / reception circuits are operated at a time so that the power supply state between the common line C and each of the line lines L1 to Ln is not inadvertently changed. The operation timing can be controlled.

  Furthermore, the specific plurality of fire detectors SE perform signal transmission output using a circuit that performs a switching operation in a low impedance state, and it is not necessary to provide an extra signal output circuit.

  Then, it is possible to distinguish between a fire signal by a switching operation that is output to the fire detector SE line and a pulse for signal transmission.

  [Automatic test is performed when the number of disconnection detection processes matches the self-address] Next, the automatic test process at the time of signal transmission in the above embodiment will be described.

  FIG. 16 shows a disconnection detection process (termination detection process) during signal transmission between the fire receiver RE1 of FIG. 2 and the fire detector SE, specifically, the fire sensor SE1 of FIG. It is a time chart which shows the relationship of an automatic test process.

  This fire detector SE1 performs automatic test processing when the number of times of receiving an operation stop command for disconnection detection processing sent from the fire receiver RE coincides with its own address.

  In FIG. 16, the fire receiver RE1 performs the polling transmission of FIG. 15 (b1 and b2 of CM1 are operation stop commands (sleep mode start command)) in order to detect disconnection of the signal line connected to the fire detector SE1. It sends out to the fire detector SE1 side (step S1).

  On the other hand, the fire detector SE1 clears the disconnection detection processing count A to 0 when the detector is activated (step S101), and receives an operation stop command from the fire receiver RE1 in this state (step S102). ), Disconnection processing. That is, the microcomputer 71 is set in the sleep mode for a predetermined period, and the current consumption is minimized (step S103).

  In this state, the fire receiver RE1 performs a disconnection detection operation by the disconnection detection circuit 15 to check whether a prescribed current is flowing in the signal line (step S2). When it is confirmed that 30 seconds have passed since the operation stop command is sent (step S3), the test result return command (CM1 of CM1) represented by the polling transmission of FIG. 10 is then sent to return the automatic test result from the fire detector SE1. b2 and b1 are "polling 1 command") to the fire detector SE1 side (step S4). Since the “polling 1 command” corresponds to the fire detector SE1 with the address AD 1-15, when the fire detector SE1 with the address AD16-30 is connected to the signal line, It is assumed that “polling 2 command” is transmitted after “polling 1 command” is transmitted.

  On the other hand, the fire detector SE1 increments the disconnection detection processing count A by 1 (step S104). If the address AD of the fire detector SE1 does not match the disconnection detection processing count A (step S105), the process proceeds to step S109. However, if the address AD of the fire detector SE1 coincides with the disconnection detection processing count A (step S105), an automatic test as described above (fire detection section sensitivity test and light receiving window contamination degree measurement test) is performed, The test result is stored in the EEPROM 91 (step S106).

  The disconnection detection processing count A does not coincide with 30 (in this case, 30 because the number of fire detectors SE1 connectable to the signal line is 30, but other values may be used). If so (step S107), the process proceeds to step S109. If the disconnection process detection count A is equal to 30 (step S107), the disconnection detection process count A is cleared to 0 (step S108).

  When a test result return command is received from the fire receiver RE1 in this state (step S109), the test result stored in the EEPROM 91 is pulse-transmitted at the slot position based on its own address in the polling transmission of FIG. 10 (step S110). ), The process returns to step S102.

  In this state, the fire receiver RE1 receives the test result from the fire detector SE1 by the signal receiving circuit 13, and detects whether the automatic test result is normal or abnormal based on the pulse width (see FIG. 13). To do. (Step S5) After confirming that 30 seconds have passed since the test result return command was sent (Step S6), the process returns to Step S1, and the disconnection detection process is performed again.

    The fire detector SE1 may perform an automatic test triggered by the fact that the number of times of receiving the operation stop command coincides with its own address, and the timing of the execution is immediately after the reception of the operation stop command. Alternatively, it may be after a predetermined time has elapsed since reception.

  In this way, only one fire detector whose number of times of receiving the operation stop command is identical to its own address among the fire detectors performs the automatic test. Therefore, the entire system at the time of performing the automatic test of the fire detector SE1. This makes it possible to accurately determine the pulse signal from the fire detector during this period on the fire receiver side, that is, by stabilizing the voltage of the signal line, that is, the entire signal line during automatic testing. Therefore, the signal line voltage does not drop during the automatic test, and the fire detection circuit of the fire receiver does not detect it as a fire signal.

It is a figure which shows P type system PS1 which is one Example of this invention. It is a block diagram which shows the structure of the fire receiver RE1 in the said Example. It is a block diagram which shows the structure of the fire detector SE1 in the said Example. FIG. 4 is a circuit diagram showing a transmission / transmission circuit 41 in FIG. 3. FIG. 4 is a circuit diagram showing a transmission / reception circuit 42 of FIG. 3. It is a circuit diagram which shows the confirmation lamp circuit 80 of FIG. It is a figure which shows the example of the command transmitted to the fire detector SE from the fire receiver RE in P type system PS1. In the said Example, it is a figure which shows the pulse which the fire receiver RE sent out. In the said Example, it is a figure which shows the pulse which the fire receiver RE sent out. It is a figure which shows the example of the polling transmission in the said Example. It is explanatory drawing of the said Example. It is explanatory drawing of the said Example. It is explanatory drawing of the said Example. It is explanatory drawing of the said Example. In the said Example, it is a time chart which shows from starting pulse generation to completion | finish of a termination | terminus detection process. 4 is a time chart showing the relationship between disconnection detection processing and automatic test processing during signal transmission between the fire receiver RE1 and the fire detector SE of FIG. 2, specifically, the fire detector SE1 of FIG.

Explanation of symbols

RE, RE1 ... Fire receiver,
SE, SE1 ... Fire detector,
PS1 ... P type system,
12 ... Signal transmission circuit,
13: Signal receiving circuit,
14 ... Fire detection circuit,
15 ... Disconnection detection circuit,
41 ... Transmission circuit,
42 ... receiving circuit,
71: Microcomputer,
81: Clock oscillation circuit.

Claims (4)

In a fire alarm system that connects multiple fire detectors equipped with an automatic test function to the signal line drawn from the fire receiver, and receives the fire signal from the fire detector for each signal line,
The above fire receiver
A disconnection detection circuit for detecting disconnection of the signal line in accordance with a voltage level of the signal line;
A transmission / reception circuit for performing signal transmission with the plurality of fire detectors via the signal line;
An operation stop command for setting each fire detector to the sleep mode is output via the signal line, and when a predetermined time has elapsed after the operation stop command is output, the disconnection detection circuit is connected to the signal line. Control means for discriminating disconnection; and
Each of the above fire detectors
When the operation stop command is received via the signal line, the sleep mode is entered, and when a predetermined time has elapsed since the operation stop command is received, the normal state is restored.
The fire alarm system is characterized in that the test is performed when the number of times the operation stop command is received coincides with its own address. In claim 1,
The above fire receiver
A test result return command for collecting the test results of the automatic test function in each of the fire detectors is output via the signal line,
Each of the above fire detectors
A fire alarm system for outputting a test result by receiving the test result return command via the signal line. In claim 1,
Each of the fire detectors is a flame detector equipped with a fire detector sensitivity test function and a light receiving window contamination degree measurement test function as the automatic test function. In fire detectors connected to signal lines drawn from fire receivers and outputting fire signals by switching operation, and equipped with automatic test function,
By receiving an operation stop command sent by the fire receiver to detect the disconnection of the signal line via the signal line, the sleep mode is entered, and a predetermined time has elapsed since the operation stop command was received. When the elapses, it returns to the normal state,
The fire detector is characterized in that the test is performed when the number of times the operation stop command is received coincides with its own address.

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