JP4308036B2 - Fire alarm system - Google Patents

Description

The present invention connects a plurality of fire detectors to a sensor line drawn from a receiver, and receives a common fire signal or a fire display signal from the fire sensor for each line, and issues a P-type fire alarm. About the system.

  Conventionally, in the fire alarm system known as P type, as shown in FIG. 16, a plurality of fire detectors 104 are connected to the sensor line 102 drawn from the receiver 100, and the fire detectors are connected in units of lines. The fire alarm is received by receiving the alarm signal from.

Also at the end of the sensor lines 10 2 monitors the disconnection at the receiver 100 by connecting a terminal resistor 106. In the disconnection monitoring by the receiver 100, if there is no disconnection in the sensor line 102, it is judged normal because a specified current flows through the termination resistor and a specified line voltage is obtained. The line voltage increases with respect to the specified voltage because no longer flows, and the increase in the line voltage is detected to determine that the line is disconnected, and a failure alarm indicating the disconnection is issued.

  However, in the conventional P-type fire alarm system, the termination resistor is connected to the end of the sensor line and the disconnection is monitored. Therefore, the current consumption for the fire detector and the current for monitoring the disconnection flowing through the termination resistor are Therefore, the current consumption of the fire detector must be kept below the current consumed by the termination resistor, which places many restrictions on the design of the fire detector.

  In addition, since current exceeding the current consumed by the fire detector must flow through the termination resistor, the current consumption of the fire alarm system increases, and there is a problem that the power supply unit provided in the receiver is enlarged.

  Furthermore, since it is essential to connect a termination resistor to the end of the sensor line, for example, a termination resistor installation space is required in the detection base of a fire detector installed at the termination. It depends.

The present invention has been made to solve such a problem, and an object thereof is to provide a fire alarm system capable of monitoring disconnection of a sensor line without requiring a termination resistor.

  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, and an alarm signal is received from a fire sensor on a line basis to alarm. Connect a fire detector for termination with a unique signal response unit that responds to the confirmation signal from the receiver to the end of the receiver, and send a confirmation signal to the receiver side for each sensor line. The present invention is characterized in that a disconnection monitoring control unit is provided which responds a unique signal from the fire detector for a fire and displays a fault by judging that the line is disconnected when there is no response of the unique signal.

  According to such a fire alarm system of the present invention, a termination fire detector provided with a unique signal response unit in place of the termination resistor is connected to the termination of the sensor line, and the disconnection monitoring control unit of the receiver periodically For example, by sending a confirmation signal so that the response time is less than 1 minute, the termination resistor is not required, reducing the current consumption of the system, and reducing the current consumption of the fire detector to less than the consumption current of the termination resistor. This eliminates the design restrictions of reducing current consumption, improves the design freedom of the fire detector, eliminates the need for installation space for the termination resistor, and eliminates installation problems.

  In another aspect of the present invention, a fire alarm system for connecting a plurality of fire detectors to a sensor line drawn from a receiver, and receiving a warning signal from the fire sensor for each line and alerting In this case, a plurality of fire detectors equipped with a unique signal response unit that responds to a confirmation signal from the receiver is connected to the sensor line, and a confirmation signal is sent to the receiver side for each sensor line. Disconnection monitoring control that sends out a specific signal from the fire sensor connected to at least the end of the sensor line, and displays a fault by judging that the corresponding sensor line is disconnected if there is no reception response to the specific signal A feature is provided.

  In this way, when all the fire detectors connected to the sensor line are fire detectors equipped with a unique signal response unit, the signal state response unit of the fire sensor located at the end is connected to the same line. By monitoring the disconnection by identifying the normal response of the fire detector connected to the terminal from the specific signal for the confirmation signal from the receiver by responding with a specific signal that is distinguished from the specific signal of other fire detectors. Can do.

  The specific signal response unit provided in the fire detector of the present invention includes a nonvolatile memory such as an EEPROM, and only one bit at a specific position is a bit distinguished from other bits at a predetermined address of the nonvolatile memory. The unique number data is stored, and the unique signal is transmitted at an output timing of a specific bit by the number data reading operation in which a predetermined address is designated by a confirmation signal from the receiver.

  For this reason, the CPU does not require a simple memory such as an EEPROM and its non-volatile memory and its interface circuit, and a simple communication control using the memory access as a transmission protocol allows the fire detector to respond with a unique signal. Compared with a so-called R-type fire alarm system using a data transmission circuit and a data transmission protocol, a significant cost reduction can be realized and the spread thereof is promoted.

  The unique signal response unit provided in the fire detector further detects the fire by detecting the number data in the non-volatile memory with the specified address specified by the confirmation signal from the receiver while the fire signal is detected. The fire signal transmission is temporarily interrupted at the output timing of the specific bit specified in. Specifically, the unique signal response unit includes an exclusive OR circuit (EX-OR circuit) that operates the alarm circuit by inputting the read response signal from the nonvolatile memory and the fire signal from the fire detection unit. .

  In another aspect of the present invention, a fire alarm system for connecting a plurality of fire detectors to a sensor line drawn from a receiver, and receiving a warning signal from the fire sensor for each line and alerting At the end of the sensor line, a terminator equipped with a unique signal response unit that responds to the confirmation signal from the receiver is connected to the end of the sensor line, and a confirmation signal is sent to the receiver side for each sensor line. It is characterized in that a disconnection monitoring control unit is provided which sends out a unique signal from a terminator and determines that the corresponding line is disconnected when there is no response signal and displays a fault.

  In this way, even when a terminator dedicated to state response that does not have a fire detector function is connected to the end of the sensor line, current consumption can be reduced, sensor design restrictions can be removed, and termination resistors can be installed. The problem can be solved.

The unique signal response unit provided in the terminator includes a nonvolatile memory such as an EEPROM, and stores unique number data in which only one bit at a specific position becomes bit 1 at a predetermined address of the nonvolatile memory. A unique signal is transmitted at an output timing of a specific bit determined specific to the terminator by the number data reading operation in which a predetermined address is designated by a confirmation signal from the terminal. In this case as well, no CPU is required, and a significant cost reduction can be realized.

  According to the fire alarm system of the present invention, the following effects can be obtained.

  First, by eliminating the termination resistor connected to the sensor line, it is no longer necessary to make the current consumption of the fire detector less than the current consumed by the termination resistor, increasing the degree of freedom in designing the fire detector. it can.

  In addition, it is no longer necessary to supply more current than that consumed by the fire detector to the termination resistor, the current consumption of the system can be reduced by the current consumption of the termination resistor, and a small power supply unit with a small power capacity can be used for the receiver power supply unit. Can be used.

Furthermore, since no termination resistor is required, the installation space is also unnecessary, and the labor of the installation work is eliminated, so that the work efficiency during the installation work can be improved.

  FIG. 1 is an explanatory diagram of a fire alarm system according to the present invention. In FIG. 1, sensor lines 18-1 to 18 -m are drawn from the receiver 1 to connect a plurality of on / off type fire sensors 2 and one terminal fire sensor 3.

  The on / off fire sensor 2 connected to the sensor lines 18-1 to 18-m includes various types of sensors such as a photoelectric smoke sensor, a semiconductor heat sensor, a differential heat sensor, and a constant temperature heat sensor. A fire detector can be connected. These on-off type fire detectors 2 send out a fire signal to the receiver 1 by short-circuiting the sensor lines 18-1 to 18-m when a fire is detected.

  In addition to the fire detection unit, the termination fire sensor 3 includes a specific signal response unit that responds a specific signal to a confirmation signal periodically transmitted from the receiver 1 during monitoring. Disconnection monitoring is performed.

  The unique signal response unit of the termination fire sensor 3 includes a nonvolatile memory such as an EEPROM, and stores unique number data in which only one bit at a specific position becomes bit 1 at a predetermined address of the nonvolatile memory. The unique signal is transmitted at the output timing of bit 1 by reading the number data based on the confirmation signal from the receiver 1.

  As the fire detection unit of the termination fire detector 3, various fire detection units such as a photoelectric smoke detection unit, a semiconductor heat detection unit, a differential heat detection unit, and a constant temperature heat detection unit can be used. .

  The receiver 1 is provided with an MPU 6. An operation unit 8, an alarm display unit 9, a district display unit 10, a transfer output unit 11, and a memory 12 are provided for the MPU 6.

  Further, monitoring circuit units 7-1, 7-2,..., 7-m are provided on the sensor line side of the MPU 6 for each line. Sensor lines L and C are drawn out from each of the monitoring circuit units 7-1 to 7-m, and a plurality of on / off type fire sensors 2 and termination fire sensors 3 are connected.

  As represented by the monitoring circuit unit 7-1, the monitoring circuit units 7-1 to 7-m include a voltage control circuit 15, an output buffer circuit 16, and a current detection circuit 17. In correspondence with the monitoring circuit units 7-1 to 7-m, the MPU 6 is provided with a function of the disconnection monitoring control unit 14 in addition to the function of the reception control unit 13.

  The reception control unit 13 of the MPU 6 detects an alarm signal for each line and performs alarm display, that is, fire representative display and district display (report line display). The disconnection monitoring control unit 14 of the MPU 6 transmits a confirmation signal for each sensor line unit to cause the termination fire sensor 3 to respond with a unique signal, and when there is a response, determines that the line is normal, and there is no response to the unique signal. In this case, it is determined that the corresponding sensor line is disconnected, and a fault is displayed.

  The confirmation signal from the disconnection monitoring control unit 14 to the termination fire sensor 3 is a read operation signal for a predetermined address of the EEPROM provided in the unique signal response unit of the termination fire sensor 3. In the read address of the EEPROM, unique number data corresponding to the sensor line in which only 1 bit at a specific position is 1 and all others are 0 is written in advance. Therefore, the termination fire detector 3 detects the unique signal at the output timing of bit 1 (bit 1 output period) by reading the unique number data specifying a predetermined address of the EEPROM by the confirmation signal from the receiver 1. Sends to the line and responds to the confirmation signal. The specific signal data of the read address of the EEPROM may be set to bit 0 only at a specific position and bit 1 at other positions.

  Transmission of the confirmation signal by the disconnection monitoring control unit 14 of the receiver 1 is performed for all lines when the number of sensor lines is small, and is sequentially transmitted in units of a predetermined number when the number of sensor lines is large. Of course, confirmation signals may be sent sequentially in units of one line. In order to quickly detect the disconnection state, it is desirable to periodically send the confirmation signal at intervals of 1 minute or less.

  The voltage control circuit 15 provided in the monitoring circuit unit 7-1 converts the clock and data required for the EEPROM reading operation of the termination fire sensor 3 into a voltage pulse signal, and the sensor via the output buffer circuit 16 Send between lines L and C. In the present invention, conversion of the data bits 0 and 1 into a voltage pulse signal is performed by pulse width modulation. Therefore, the end fire detector 3 side detects data bits 0 and 1 from the pulse width of the received voltage pulse signal. Further, the output buffer circuit 16 changes the voltage between the sensor lines L and C from 18 bottles at the time of monitoring to 24 volts and sends out a voltage pulse signal.

  FIG. 2 is a circuit block diagram showing an embodiment of the termination fire sensor 3 of FIG. The terminal fire detector 3 is provided with a rectification / noise absorption circuit 21, an alarm circuit 22, a power supply circuit 24, a signal processing circuit 25, and a detection circuit 26 following the connection terminals L and C of the sensor line.

  The detection circuit 26 outputs a detection signal corresponding to smoke or heat from the fire to the signal processing circuit 25. The signal processing circuit 25 outputs, for example, a fire signal E2 to the alarm circuit 22 when the detection signal from the detection circuit 26 exceeds a predetermined fire determination threshold value, and is an EX-OR circuit that will be clarified in later explanation. By switching the transistor 23 by the output of 32, a reporting current Ic determined by a resistor R is caused to flow between the sensor lines L and C, thereby sending a reporting signal to the receiver side.

  In addition, when the detection circuit 26 is a scattered light type smoke detection circuit that detects scattered light due to smoke by intermittent light emission of a light emitting element, for example, the signal processing circuit 25 is triggered by 2 counts of fire detection signals obtained by intermittent light emission. The circuit 22 is operated to send an alarm signal. In the heat detection of a thermistor or the like, the alarm circuit 22 is operated to output an alarm signal when the comparator exceeds a fire determination threshold.

In addition to such a basic circuit of the termination fire detector 3, in the present invention, the unique signal response unit 27 is provided corresponding to the disconnection monitoring control function on the receiver 1 side. Specific signal response unit 27, a clock detection circuit 28, the data detection circuit 29, and a chip select detection circuit 30, EEPROM 31 and EX-OR circuit as a non-volatile memory (exclusive OR circuit) 32.

  The clock detection circuit 28 inputs a voltage pulse signal that changes the voltage of 18 to 24 volts between the sensor lines based on the confirmation signal from the disconnection monitoring control unit 14 provided in the MPU 6 of the receiver 1 of FIG. A clock pulse synchronized with the voltage pulse signal is detected and output to the EEPROM 31.

  The data detection circuit 29 receives the voltage pulse signal based on the confirmation signal from the receiver, detects the data bits 0 and 1 by determining the pulse width of the voltage pulse signal, and the operation code and address for the read operation of the EEPROM 31 The data bit indicating the data output timing is output.

  The chip select circuit 30 receives a voltage pulse signal between the sensor lines, outputs a chip select detection signal over the time when the voltage pulse signal is obtained, and performs a chip select for the reading operation of the EEPROM 31.

  FIG. 3 is a time chart of the detection operation of the data detection circuit 29 and the chip select detection circuit 30 of FIG. 2 for the voltage pulse signal between the sensor lines. FIG. 3A shows a voltage pulse signal corresponding to a confirmation signal transmitted from the receiver to the sensor line, and a voltage pulse is transmitted by changing 18 volts during monitoring to 24 volts.

Although this voltage pulse signal has a period T, pulse width modulation is performed to change the time of the latter L level interval according to data bits 1 and 0. For example, when the data bit “1001” is transmitted from the receiver, the time of the L level section in the second half of the pulse signal having the period T is set to T ₁ time for the bit 1, while the second L level of the data bit 0 is set. The section time is set to a shorter T ₀ time.

Therefore, in the data detection circuit 29 of FIG. 2, the L level time is monitored for each pulse of the input voltage pulse signal, and if it is T ₁ time, the data bit 1 is transferred in the next pulse cycle as shown in FIG. If it is T ₀ time, data bit 0 is output in the next cycle.

  On the other hand, in the chip select detection circuit 30 of FIG. 2, in FIG. 3A, the voltage between the sensor lines LC first increased from 18 volts at the time of monitoring to 24 volts by sending a voltage pulse signal. This is detected, and the chip select signal is turned on to H level as shown in FIG.

Thereafter, when the time during which the voltage between the sensor lines is 18 volts at the time of monitoring continues for T ₂ hours longer than T ₁ time used for determination of data bit 1, FIG. The chip select detection signal falls from H level to L level as shown in FIG. As a result, while the voltage pulse signal is obtained from the receiver, the chip select detection signal is turned on when the signal is at the H level, and the chip select operation of the EEPROM 31 is performed.

Incidentally determination of T _0, T _1, T ₂ hours in the voltage pulse signals between sensor lines in FIG. 3 (A), the time constant of the time constant circuit using a resistance and a capacitor T _0, T _1, T ₂ Corresponding to the time, the charging voltage of the capacitor is detected by determining with a comparator or the like, or the clock pulse for time measurement is counted by the counter over the L level section (18 volt section) of the voltage pulse signal. If the count value is T ₀ time, data bit 0, T ₁ time data bit 1, and T ₂ time, chip select detection signal is turned off.

  Next, the EEPROM 31 provided in the unique signal response unit 27 in FIG. 2 will be described. The EEPROM 31 can store 32-bit data D0 to D31 for each address. In the EEPROM 31 of the present invention, number data for responding a unique signal to the confirmation signal from the receiver 1 is stored at a specific address, for example, “address 38”. As the number data of the address 38, bit 1 is stored in one specific bit among the 32 bits of data bits D0 to D31, and the remaining bits are all set to bit 0.

  FIG. 4 shows EEPROMs 31-1 to 31 -m provided in the termination fire sensor 3 connected to the sensor lines 18-1 to 18 -m of FIG. The position of bit 1 is indicated by hatching. That is, the number data stored in the addresses 38 of the EEPROMs 31-1 to 31-m corresponding to the sensor lines 18-1 to 18-m are the data bits D31, D30,. -The position is shifted sequentially for each line, such as D0.

  In the reading operation of the EEPROMs 31-1 to 31-m, among the data bits D0 to D31 of the number data, bit output is performed in the order of the data bits D31 to D0 in synchronization with the clock (serial bit output).

  For this reason, as shown in FIG. 4, number data obtained by sequentially shifting the storage bit position of bit 1 is stored in the addresses 38 of the EEPROMs 31-1 to 31-m corresponding to the sensor lines 18-1 to 18-m. Then, based on the confirmation signal designating the reading operation of the address 38 from the receiver 1, the EEPROMs 31-1 to 31-m of the termination fire detectors 3 of all the lines are simultaneously read out, and the unique signals are responded in order. be able to.

  FIG. 5 shows a list of outputs to the inputs of the response signal E1 and the fire signal E2 by the EX-OR circuit 32 of FIG. 2 and an upstream signal by the alarm circuit 22 based on the output of the EX-OR circuit 32. In FIG. 5, in the state where the confirmation signal is not output from the receiver 1 at the time of monitoring, both the response signal E1 and the fire signal E2 are L level, and the output of the EX-OR circuit 32 is also L level. The current as an upstream signal is zero.

  When the EEPROM 31 receives the confirmation signal from the receiver 1 during monitoring and sets the response signal E1 to the H level by reading out the specific data bit 1 at the address 38, the fire signal E2 is at the L level at this time. The output of the -OR circuit 32 becomes H level. When the output of the EX-OR circuit 32 becomes H level, the transistor 23 of the alarm circuit 22 is switched, and the alarm current Ic determined by the resistance R is caused to flow between the sensor lines L-C. Is sent to the receiver 1 as a unique signal.

  On the other hand, in the event of a fire, when the fire signal E2 is H level and the response signal E1 is L level, the output of the EX-OR circuit 32 is H level, and the transistor 23 of the alarm circuit 22 is switched. An alarm current Ic determined by the resistor R is sent as an upstream signal between the sensor lines L-C, and a fire alarm signal is sent to the receiver 1.

  When a confirmation signal is sent from the receiver 1 during the fire alarm, the response signal E1 output from the EEPROM 31 becomes H level at the read timing of the data bit 1, and therefore the output of the EX-OR circuit 32 is the response signal. During the period during which E1 is being output, it becomes L level, and the transistor 23 of the alarm circuit 22 is restored to OFF so that there is no upstream signal in which the alarm current is temporarily set to zero.

  Therefore, on the receiver 1 side, even when the fire alarm signal is being received, the alarm signal is temporarily interrupted during that time, so that the inherent signal for the confirmation signal from the fire detector 3 for termination is unique. It can be recognized that the response is a signal.

  FIG. 6 is a timing chart showing the response operation of the specific signal to the confirmation signal from the receiver 1 of FIG. 1 with respect to the termination fire sensor 3 of FIG. In FIG. 6, for the sake of simplicity of explanation, a case where a confirmation signal is transmitted only to the sensor line 18-1 drawn from the monitoring circuit unit 7-1 of the receiver 1 is taken as an example. Yes.

6A shows a voltage pulse output from the monitoring circuit unit 7-1 to the sensor line 18-1 based on the confirmation signal from the disconnection monitoring control unit 14 provided in the MPU 6 of the receiver 1 of FIG. The voltage pulse signal is output by changing the voltage of 18 volts at the time of monitoring to 24 volts, and the voltage pulse signal is a data bit as shown in FIG. The pulse width modulation is performed with the L level time of 18 volts as T ₁ time for ₁ and the L level time of 18 volts as T ₀ time shorter than that for data bit 0, and a voltage pulse signal is transmitted. Yes.

  The voltage pulse signal of the sensor line 18-1 is input to the clock detection circuit 28 of the termination fire sensor 3 of FIG. 2, and a clock signal synchronized with the voltage pulse signal as shown in FIG. Detected and supplied to the EEPROM 31 as a clock.

  Here, the clock signal of FIG. 6B has the same pulse width as that of the voltage pulse signal subjected to pulse width modulation. However, since the clock signal operates with its rising timing being effective, The difference is not particularly a problem.

  Since the first half of the voltage pulse signal is a dummy clock, a start bit, a read operation code, and an address bit as shown in FIG. 6D, pulse width modulation corresponding to data bits 0 and 1 representing this is performed. However, since only the clock timing is given to the data bit used for the serial read output of 32-bit data of the EEPROM 31 in the latter half, the voltage pulse signal having a normal clock with a duty of 50% is applied to that portion. In synchronization with this, the clock in FIG. 6B also detects a clock pulse with a duty of 50%.

Also, as shown in FIG. 6C, the chip select detection circuit 30 detects the voltage increase from the first 18 volts to 24 volts of the voltage pulse signal in FIG. 6A and turns the chip select signal to the H level. and, the chip select signal is time to return to 18 volts, the monitoring is interrupted voltage pulse signal is turned off to the L level is reached T ₂ hours of FIG.

  FIG. 6D shows data detected by the data detection circuit 29. From the top, the dummy clock “00”, the start bit “1”, the read operation code “10”, the address bit “100110” (address 38), and 32 The read timing corresponding to the bit data bits D31 to D0 is output.

  Of the 32-bit data bits D31 to D0, the termination fire detector 3 stores data bits 1 in advance as hatched lines in the data bits D31 as in the EEPROM 31-1 in FIG. The remaining data bits D30 to D0 store data bit 0, and the read bit output of data bit D31 storing data bit 1 is a response signal E1 output from EEPROM 31-1.

  Therefore, at the time of monitoring, as shown in FIG. 6E, the read bit output of the first data bit D31 storing bit 1 is input to the EX-OR circuit 32 with the response signal E1 as H level, The output is set to the H level, the transistor 23 of the alarm circuit 22 is switched, and the alarm current Ic determined by the resistance R is used as a response current at the time of monitoring as shown in FIG. As a result, the termination fire sensor 3 responds with a specific signal to the confirmation signal from the receiver 1.

  On the other hand, when a fire is detected by the termination fire detector 3 itself, the fire signal E2 output from the signal processing circuit 25 when the fire is detected becomes H level, and at this time, the response signal E1 is L level. The output of the EX-OR circuit 32 becomes H level, the transistor 23 of the alarm circuit 22 is switched, and the alarm current Ic determined by the resistor R is continuously detected from the time of the fire as shown in FIG. The alarm signal is sent to the line 18-1 and sent to the receiver.

  When a confirmation signal is output from the receiver 1 during such a fire alarm, the response signal E1 becomes H level at the bit output timing of the data bit D31 in FIG. 6D, and at this time the fire signal E2 Since the output of the EX-OR circuit 32 is at the L level during the reading period of the data bit D31, the transistor 23 is turned off, and the alarm current is temporarily output as shown in FIG. As a result, the receiver 1 can recognize the response of the unique signal from the terminating fire sensor 3 to the confirmation signal.

  On the other hand, when the fire alarm is issued by the other on / off type fire sensor 2 connected to the same line instead of the terminal fire sensor 3, the alarm current generated by the other on / off type fire sensor 2 is changed. The response current of the specific signal with respect to the confirmation signal of the termination fire detector 3 flows in a superimposed manner, and from this temporary increase in the fire alarm current, the receiver 1 receives the normal unique signal from the termination fire detector 3. Can be recognized.

  Note that the timing chart of FIG. 6 shows an example in which the read-out operation of the EEPROM 31 is performed with respect to the confirmation signal from the receiver and a normal unique signal is responded even when a fire is triggered. The disconnection monitoring operation may be temporarily interrupted. For example, the disconnection monitoring control at the time of the fire alarm may be interrupted by, for example, recognizing the reception of the fire alarm by the disconnection monitoring controller 14 of the receiver 1 and interrupting the transmission of the confirmation signal. Of course, whether or not to perform confirmation and response for disconnection monitoring at the time of fire alarm can be selected as appropriate.

  In the timing chart of FIG. 6, the case where the confirmation signal is transmitted only from the monitoring circuit unit 7-1 of the receiver 1 of FIG. 1 is taken as an example, but actually, the monitoring circuit unit 7 of the receiver 1 is used. -1 to 7-m simultaneously send confirmation signals to the termination fire detectors 3 of the respective sensor lines, and the unique signal response unit 27 provided in each termination fire sensor 3 operates simultaneously. As shown in EEPROM 31-1 to 31-m in FIG. 4, the response current of the unique signal is sent at the read timing of bit 1 at a different position in the 32-bit data that is the number data stored in the same address 38. Accordingly, the response current between the sensor lines L-C is sequentially transmitted at each timing of the data bits D31 to D0 corresponding to the number of sensor lines.

  Further, when the number of sensor lines drawn from the receiver 1 in FIG. 1 exceeds 32 bits, which is the number of data bits of the EEPROM 31 provided in the termination fire detector 3, a different address for every 32 lines. Is used. In this case, the confirmation signal from the receiver 1 may be sent out sequentially for each address of 32 lines.

  Note that the storage position of the specific bit for termination does not necessarily have to be sequentially shifted for each sensor line, and a bit position common to all the fire detectors for termination may be set. In this case, when confirmation signals are sent to all the sensor lines at the same time, responses are made at the same timing from all the sensor lines.

  However, since they are connected to different sensor lines, it is possible to correctly monitor disconnection of all the sensor lines even if the bit storage positions are the same. In this case, the monitoring circuit unit 7 can monitor disconnection simultaneously for all the lines by inputting a response signal to the MPU 6 using different ports.

  Alternatively, if it is determined whether the response signal is received at the specific bit position once in the monitoring circuit unit 7 before being input to the MPU 6, and then distributed processing is performed so as to transmit the result to the MPU 6, disconnection monitoring of all lines simultaneously It can be performed.

  As described above, if the storage position of the specific bit is determined in advance, it becomes easy to set the bit in the EEPROM 31 of the termination fire sensor 3, and the receiver 1 can determine the predetermined bit position for termination for each sensor line. The disconnection can be easily determined depending on whether the response signal is received.

  In addition, when the disconnection monitoring is performed on the sensor lines one by one instead of simultaneously with all the lines, the disconnection monitoring of all the lines can be performed in order using the common input port of the MPU 6.

  The receiver 1 stores the disconnection monitoring bit position, and when there is no response of the response signal to the specific signal from the sensor at the specific bit position for the termination sensor with respect to the confirmation signal transmitted from the receiver 1. It is determined that the sensor line is disconnected, and a fault alarm is output. Note that the storage position of the specific bit may be changed and set for each group, and a confirmation signal may be transmitted for each of the plurality of sensor lines.

  Further, in the embodiments of FIGS. 3 and 6, the confirmation signal transmitted from the receiver transmits data bit 1 or bit 0 with the L level time constantly changed every period, but this is not restrictive. For example, as shown in FIG. 7, data bits 1 and 0 are output to the sensor line by pulse width modulation in which the L level time is not common but is constant and the H level time is changed thereafter. Also good.

  FIG. 8 is an explanatory view showing another embodiment of the fire alarm system according to the present invention. In this embodiment, a fire sensor other than the termination fire sensor connected to the sensor line is also shown in FIG. It is characterized by having a fire detector equipped with a unique signal response unit.

  8, the configuration of the fire receiver 1 is basically the same as that of the embodiment of FIG. 1, and the disconnection monitoring control unit 14 provided in the MPU 11 sends a confirmation signal for disconnection monitoring to the fire alarm system. 7-1 through 7-m are sent to the sensor lines 18-1 to 18-m, the response of the unique signal is judged to be normal, and if the unique signal cannot be received, it is judged as a disconnection and a failure An alarm is issued.

  The detector lines 18-1 to 18-m from the receiver 1 include a plurality of fire detectors 4-11 to 4-m, n-1 having a specific signal response unit for a fire response, in addition to the fire response. Terminal fire detectors 5-1n, 5-2n,..., 5-mn, each having a specific signal response unit that responds to a specific signal for monitoring disconnection are connected.

  FIG. 9 shows data stored in the EEPROM 31 provided in the fire detector 4 and the terminating fire detector 5 of the sensor line drawn from the receiver 1 of FIG. FIG. 9 shows the stored contents of the number data by taking out the EEPROM 31-1 to 31-mn of the fire detectors and termination fire detectors provided on each line divided into the sensor lines 18-1 to 18-m. ing.

  For example, when looking at the top sensor line 18-1, the non-volatile memory 31- corresponds to the fire sensors 4-11 to 4-1, n-1 and the termination fire sensor 5-1n. 11-31-11n exists. The bit positions of the number data stored in the addresses 38 of the EEPROMs 31-11 to 31-1n are set with unique bits such as data bits D0, D1,... D31 so as not to overlap in the sensor line. .

  A common end bit position D31 is set for each end fire detector 5. The receiver 1 stores the number of fire detectors connected to the line or the set bit position for each fire detector, and determines whether the fire detector receives a response signal correctly by sending a confirmation signal. Check the sensor line status.

  The receiver 1 includes the fire detectors 4-11 to 4-m-1, n connected to the sensor lines 18-1 to 18-m, including the fire detectors 5-1n to 5-mn for termination. A confirmation signal which is a read signal of the address 38 is sent. For this reason, the receiver 1 determines that the operation of the sensor corresponding to the bit position is normal by sequentially returning response signals at the bit positions set uniquely to the sensor, and is further predetermined. If a response signal is sent at the bit position for the termination sensor, it is possible to determine whether the termination sensor is normal and the disconnection state of the sensor line.

  On the other hand, when no reply signal is returned at the bit position set for each sensor, the corresponding fire sensor is abnormal and outputs a fault signal. If no reply signal is returned at the termination bit position, it is determined that the sensor line is disconnected, and a fault alarm is output. In addition, when any of the sensors is activated, a notification current flows through the sensor line. At this time, a confirmation signal, which is a read signal of the address 38 from the receiver 1, is sent and the detected sensor senses. The alarm detector can be specified by controlling the current Ic to 0 at the transmission bit position unique to the device.

  FIG. 10 is a circuit block diagram showing another embodiment of the fire sensor 4 and the termination fire sensor 5 connected to the sensor line of FIG. The fire detector of FIG. 10 may be applied to both the fire detectors 2 and 4 and the terminal fire detectors 3 and 5 of FIGS. 1 and 8, or only one of them. Also good.

  In FIG. 10, the termination fire detector 5 is a basic fire detection circuit diagram, like the termination fire detector 3 in FIG. 2, as a rectification / noise absorption circuit 21, an alarm circuit 22, a power circuit 24, signal processing. A circuit 25 and a detection circuit 26 are provided. In addition to this, a unique signal response unit 27 is provided for responding a unique signal to a confirmation signal for monitoring disconnection during monitoring from the receiver 1.

  When the fire detector 5 further detects a fire and sends a notification signal to the receiver 1, the specific signal response unit 27 sends a fire response signal to the search signal from the receiver 1. It also has a sending function. The unique signal response unit 27 is provided with a clock detection circuit 28, a data detection circuit 29, a chip select detection circuit 30, an EEPROM 31 as a nonvolatile memory, and an EX-OR circuit 32, and this point is the same as the embodiment of FIG. In addition, a notification detection circuit 41 is further provided.

  The alarm detection circuit 41 detects the alarm status from the voltage between the sensor lines when a fire alarm signal is transmitted by the fire detector 4 on the other line, and signal processing is performed. The operation of the circuit 25 is inhibited, and the reading operation of the fire response signal for the search control signal from the receiver by the EEPROM 31 is inhibited.

  As a result, among the plurality of fire detectors 4 and the terminating fire detector 5 connected to the same sensor line, only the fire detector that has been triggered by the first detection of the fire is set to output the fire alarm signal. Only the fire response to the search control is performed, and the output of the fire alarm signal and the transmission of the fire response signal to the search control are prohibited in the fire detector that detects the second and subsequent fires.

  When the fire sensor of FIG. 10 is applied to the fire sensor 4 and the terminal fire sensor 5 of FIG. 8, the contents stored in the EEPROMs 31-1 to 31-mn of each fire sensor are the same as those of FIG. .

  FIG. 11 is a timing chart of the response operation of the specific signal to the confirmation signal from the receiver 1 with respect to the fire sensor 4 and the termination fire sensor 5 of FIG. 10, and is provided in the sensor line 18-1 of FIG. The operation of the termination fire sensor 5-1n is taken as an example.

The voltage pulse signal between the sensor lines L-C in FIG. 11A is periodically transmitted based on the confirmation signal from the disconnection monitoring control unit 14 of the receiver 1 and is 24V with the monitoring voltage 18V as the base voltage. It is a voltage pulse signal that changes between. This voltage pulse signal corresponds to the data bits 0 and 1, and as shown in FIG. 3A, for the 18 V section (L level time) in the latter half of the period T, bit 1 is T ₁ time, bit 0 is This is a signal subjected to pulse width modulation with T ₀ time.

  With respect to the voltage pulse signal between the sensor lines, the clock signal of FIG. 11B is detected by the clock detection circuit 28, and the chip select detection signal of FIG. 11C is detected by the chip select detection circuit 30, While the chip select detection signal is ON, the chip select state in which the EEPROM 31 operates is set.

  At the same time, the data detection circuit 29 detects data bits as shown in FIG. This data bit includes a dummy clock “00”, a start bit “1”, a read operation code “10”, address bits A5 to A0 when monitoring, an address bit “100110” indicating the address 38, and an acknowledgment data bit D31. It is composed of 32-bit data bits D31 to D0 that provide read timing.

  In the fire detector 5-1n for the termination of the sensor line 18-1, as shown in the last EEPROM 31-1n of the sensor line 18-1 in FIG. 9, the bit 1 is set to the data bit D31 of the address 38. Since it is stored, bit 1 is read at the timing of data bit D31 in FIG. 11D, and at this time, fire signal E2 from signal processing circuit 25 in specific signal response unit 27 in FIG. 10 is at L level. When the response signal E1 from the EEPROM 31 becomes H level, the output of the EX-OR circuit 32 becomes L level, the transistor 23 of the alarm circuit 22 is switched, and the response current Ic determined by the resistor R is applied to the sensor line L. A unique signal corresponding to the confirmation signal for disconnection monitoring is sent to the receiver 1 by flowing between -C.

  The response operation of the specific signal with respect to the confirmation signal in the terminating fire sensor 5-1n of the sensor line 18-1 is the fire detectors 4-11 to 4-1 connected to the sensor line 18-1. n-1 is also performed at the same time, and the storage location of bit 1 of address 38 is different from data bits D30... D0 as in EEPROMs 31-11 to 31-1, n-1 in FIG. Thus, in response to the bit output at the position corresponding to bit 1, the response of the unique signal is sequentially performed in the order of the fire detectors 4-1, n-1 to 4-11, and at the time of monitoring in FIG. Like the response current, a response current synchronized with the bit 1 output of the data bit flows between the sensor lines, and this is received by the receiver 1, and the presence or absence of a specific signal response is checked for each sensor line. For a specific sensor line If there is no response signal present, it is judged that the disconnection its sensor lines occurs, thereby issuing a failure alarm.

  In addition, in the data bits D0 to D30 other than the terminal, if a response signal that should come if normal is not received, it is determined that the corresponding fire sensor 4 is out of order, and a fault alarm is output.

  The stored data at the address 38 of the EEPROM in FIG. 9 is an example in which the number of fire detectors provided on each line corresponding to the data size of 32 bits is 32. The maximum number of fire detectors that can be connected to one line is the maximum configuration. If the number is other than the maximum configuration, each sensor line can have as many fire detectors as necessary. The fire detector located at the end may be used as the end fire detector.

  On the other hand, when a fire is detected by the terminating fire sensor 5-1n of the sensor line 18-1, and the fire signal E2 becomes H level from the signal processing circuit 25 of FIG. Since E1 is at L level, the output of the EX-OR circuit 32 becomes H level to switch the transistor 23 of the alarm circuit 22, and the alarm current Ic determined by the resistance R is caused to flow between the sensor lines.

  When a fire alarm is generated in such a termination fire sensor 5, the other fire sensors 4-11 to 4-1 and n-1 connected to the same sensor line 18-1 Each of the alarm detection circuits 41 detects a fire alarm by another fire sensor, suppresses the operation of the signal processing circuit 25 and the EEPROM 33, and prohibits alarms due to the second and subsequent fire detection on the same line.

  For example, when an upstream signal serving as a fire alarm is sent from the termination fire detector 5-1n to the receiver 1, the fire reception control unit 13 provided in the MPU 6 of the receiver 1 is connected to the sensor line 18-1. Recognize fire alarms and issue fire alarms. At the same time, the reception control unit 13 outputs a search control signal to search for the alarm detector on the sensor line 18-1.

  This search control signal is the same as the confirmation signal for disconnection monitoring control. In response to the search control signal from the receiver 1, the termination fire sensor 5-1n that detects a fire in the sensor line 18-1 is an EEPROM 31 shown at the end of the sensor line 18-1 in FIG. -1m, bit 1 is stored in the specific data bit D31 of the address 38, and the response signal E1 from the EEPROM 31-1m becomes H level at the timing of the bit output of the data bit D31 of the address 38. Since the fire signal E2 is also at the H level, the output of the EX-OR circuit 32 becomes the L level, and the alarm current that becomes the upstream signal is stopped while the transistor 23 of the alarm circuit 22 is outputting 1 bit.

  As a result, as shown in the response current at the time of fire in FIG. 11 (F), the response current becomes 0 for one bit section at the read timing of the data bit D31 in FIG. 11 (D), and this is recognized on the receiver 1 side. It can be recognized that the fire detection is performed by the terminating fire detector 5 of the sensor line 18-1.

  On the other hand, the fire detectors 4-11, 4-12,... That do not detect fire in the sensor line 18-1 are shown in EEPROMs 31-11, 31-12,. Thus, the address 38 is read by the search control signal as described above. However, the alarm detection circuit 41 provided in the specific signal response unit 27 detects the alarm by the other fire detector and reads the EEPROM. Since the operation is suppressed, no response is made from a fire detector that has not detected a fire to the search control signal accompanying the fire alarm.

  Note that even when a fire detector that is not at the end first detects and fires, a fire is detected at a unique data bit position set in advance in the fire detector 4 that has detected a fire in the reading operation of the address 38 as described above. By suppressing the reporting current by 1 bit, the receiver 1 can identify the fire detector 4 that has detected the fire, and can display a warning in detail on the location of the fire.

  At this time, the fire detector 4 that has not detected a fire and the fire detector 5 at the end do not send an upstream signal to the receiver 1 by the operation of the alarm detection circuit 41, so the fire detector that has detected the fire is specified. can do.

  If the number connected to one sensor line is larger than the number of data bits 32, not all addresses 38 of the EEPROM 31 are allocated. In this case, another address of the EEPROM 31, for example, the address 39 is used. The remaining fire detectors may be bit set.

  In addition, in FIG. 4, in the normal monitoring state, the function test of the fire detector 4 is not necessary, and only the disconnection monitoring is performed by sending a confirmation signal only to the termination fire sensor. If it is sufficient to perform the operation at intervals longer than the disconnection monitoring, as shown in the EEPROM address and stored data in FIG. 12, there are two reading addresses 38 for disconnection monitoring and read addresses 39 for sensor function test. Set, and at the time of normal disconnection monitoring, a response signal is received only from the termination fire detector 5 by transmitting the confirmation signal at the address 38, and a function test is performed to check whether the operation of the fire detectors 4 and 5 is normal. In the case of performing the test, a test may be performed by receiving a response signal for each bit allocated from each fire detector in a read operation using the address 39.

  FIG. 13 is an explanatory view showing another embodiment of the fire alarm system according to the present invention. In this embodiment, a terminator having an inherent signal response unit is connected to the end of the sensor line. And

  13, the configuration of the receiver 1 is the same as that of the embodiment of FIG. 1, and a plurality of on / off type fire detectors 2 are connected to the sensor lines 18-1 to 18 -m drawn from the receiver 1. The terminator 42 according to the present invention is connected to the ends of the sensor lines 18-1 to 18-m.

  FIG. 14 is a block diagram showing an embodiment of the terminator 42 of FIG. The terminator 42 has the EX-OR circuit 32 removed in addition to the signal processing circuit 25 and the detection circuit 26 for fire detection provided in the termination fire sensor 3 of FIG. This is the same as the embodiment. The storage state of the EEPROM number data provided in the terminator 42 connected to the sensor lines 18-1 to 18-m is the same as in FIG.

  14 is connected to the end of the sensor line from the receiver as shown in FIG. 13, and the disconnection monitoring control unit 14 provided in the MPU 6 of the receiver 1 is connected. By sending a confirmation signal periodically at the time of monitoring, the terminator 42 can make a unique signal respond.

  FIG. 15 is a timing chart of the response operation of the unique signal by the terminator 42 when the confirmation signal is sent from the receiver 1 to the terminator 42 in FIG. 14, and the response of the termination fire sensor at the time of monitoring in FIG. The operation can be the same as the operation.

  The specific bit of the EEPROM 31 of the terminator 42 in FIG. 12 may be set to a specific bit common to all the sensor lines 18-1, 18-2,..., For example, the data bit D31. Since it is a line, it is possible to correctly monitor disconnection of all sensor lines. Moreover, the fire detector 2 of FIG. 12 may be a fire detector having the unique signal response unit 27 shown in the above-described embodiment.

  The bit specific to the sensor output from the EEPROM is not limited to 1, but the reverse specific bit may be set to 0 and all other bits may be set to 1, so that the specific bit can be detected in the receiver. It only has to be like this.

  In addition, a setting unit for switching the function of the specific signal response unit 27 between valid and invalid may be provided in the sensor so that the sensor can be used for both termination and non-termination. Alternatively, the non-termination sensor may be shared by setting the EEPROM without specific bits, for example, all zeros.

  In the above embodiment, the disconnection is determined by receiving an upstream signal from the receiver by calling the EEPROM addressing of each fire detector from the receiver. However, the present invention is not limited to this communication method. Is provided with a CPU and stores information as the final terminal, and the disconnection of the sensor line may be detected based on whether or not there is an uplink signal by call transmission from the receiver to the final terminal.

For example, if the address dedicated to the final terminal is set in the terminal and there is no reply signal from the receiver by calling the terminal designating the address dedicated to the final terminal, it is possible to determine the disconnection of the sensor line.

Explanatory drawing of the fire alarm system of the present invention in which a fire detector having a unique signal response unit is connected to the end. Block diagram of the fire detector for termination in FIG. Time chart of data detection processing by the data detection circuit of FIG. Explanatory drawing of the data storage state of the EEPROM provided in the termination fire detector of FIG. Explanatory drawing of the logical table of specific signal response and fire alarm by EX-OR circuit of FIG. Timing chart of specific signal response operation by EEPROM reading in fire detector of FIG. Time chart of other data detection processing by the data detection circuit of FIG. 2 when the EEPROM read clocks are uneven. Explanatory drawing of the fire alarm system of the present invention in which the fire detector connected to the sensor line is a fire detector having a specific signal response unit. Explanatory diagram of EEPROM address and stored data in FIG. Block diagram of another embodiment of the fire detector of FIG. Timing chart of specific signal response operation by reading EEPROM in fire detector of FIG. Explanatory diagram of another embodiment of EEPROM address and stored data Explanatory drawing of the fire alarm system of the present invention using a terminator provided with a specific signal response unit Block diagram of the terminator of FIG. Timing chart of proper signal response operation by reading EEPROM in the terminator of FIG. Illustration of a conventional P-type fire alarm system

Explanation of symbols

1: Receiver 2: On-off type fire detector 3, 5: Fire detector for termination 4: Fire detector 6: MPU for receiver
7-1 to 7-m: monitoring circuit unit 8: operation unit 9: alarm display unit 10: district display unit 11: message output unit 12: memory 13: reception control unit 14: disconnection monitoring control unit 15: voltage control circuit 16: output buffer circuit 17: current detection circuits 18-1 to 18-m: sensor circuit 21: rectification / noise absorption circuit 22: alarm circuit 24: power supply circuit 25: signal processing circuit 26: detection circuit 27: specific signal Response unit 28: clock detection circuit 29: data detection circuit 30: chip select detection circuit 31: EEPROM (nonvolatile memory)
32: EX-OR circuit 33-1 to 33-mn: sensor line 41: alarm detection circuit 42: terminator

Claims (3)

In a fire alarm system that connects a plurality of fire detectors to a sensor line drawn from a receiver and receives a warning signal from the fire sensor for each line,
Wherein the end of the sensor lines, connecting the terminating fire detector having a unique signal response unit for responding a unique signal to the confirmation signal from the receiver,
A disconnection which sends a confirmation signal to the receiver side in units of the sensor line and makes a specific signal respond from the fire detector for termination and determines that the line is disconnected when there is no response of the specific signal and displays a fault A monitoring control unit is provided ,
The unique signal response unit includes a nonvolatile memory that stores unique number data in which only one bit at a specific position is distinguished from other bits at a predetermined address,
If a fire signal is not sent before the number data is read out from the non-volatile memory that starts the response by the confirmation signal from the receiver and designates the predetermined address, it is determined to be specific to the sensor. A unique signal is sent at the output timing of a specific bit,
When the fire signal is transmitted until the reading operation of the number data is started, a response to the specific signal is made by temporarily interrupting the transmission of the fire signal at the output timing of the specific bit. Fire alarm system.
In a fire alarm system that connects a plurality of fire detectors to a sensor line drawn from a receiver and receives a warning signal from the fire sensor for each line,
A plurality of fire detectors having a specific signal response unit that responds to a specific signal to the confirmation signal from the receiver is connected to the sensor line,
When the receiver side sends a confirmation signal in units of the sensor line to respond at least to the specific signal from the fire sensor connected to the end of the sensor line, it corresponds when there is no reception response of the specific signal Establishing a disconnection monitoring control unit that displays faults by judging that the sensor line is disconnected ,
The unique signal response unit includes a nonvolatile memory that stores unique number data in which only one bit at a specific position is distinguished from other bits at a predetermined address,
If a fire signal is not sent before the number data is read out from the non-volatile memory that starts the response by the confirmation signal from the receiver and designates the predetermined address, it is determined to be specific to the sensor. A unique signal is sent at the output timing of a specific bit,
When the fire signal is transmitted until the reading operation of the number data is started, a response to the specific signal is made by temporarily interrupting the transmission of the fire signal at the output timing of the specific bit. Fire alarm system.
3. The fire alarm system according to claim 1 , wherein the specific signal response unit operates the alarm circuit by inputting a read response signal from the nonvolatile memory and a fire signal from the fire detection unit. A fire alarm system comprising an OR circuit (EX-OR circuit).

Images