JP3849079B2 - Fire detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fire detector that performs a fire detection operation using a fire detection unit that detects a physical quantity based on a fire phenomenon, and transmits a fire signal and an analog signal.
[0002]
[Prior art]
Conventionally, when a thermal detector is configured using a thermistor and a microcomputer as a fire detector, current consumption increases as compared to a thermal detector using a bimetal or an air chamber. As a result, the number of sensors connected is limited at present, and in order to install many sensors, it is necessary to provide a large power supply device.
[0003]
[Problems to be solved by the invention]
In general, a microcomputer used for a fire detector consumes a current of several hundred μA during a calculation called a run state. On the other hand, in the stop state, which is the memory storage state when the microcomputer is in the clock stop state, the current becomes several μA, and a very low consumption state can be achieved. However, in order to shift from the stop state to the run state, it is necessary to give some signal. For example, if the oscillation circuit is configured with a frequency divider and a necessary trigger time is generated, the microcomputer itself has a low current consumption. However, current is consumed in the oscillation circuit.
[0004]
The first invention of the present application is to obtain a low-consumption fire detector using a stop state of a microcomputer or the like.
[0005]
In addition, when performing a fire monitoring operation by repeating the stop state and run state of the microcomputer, it is not possible to distinguish between the stop state and the run state when performing inspection input. The operation cannot be performed.
[0006]
The second invention of the present application is to obtain a fire detector that shifts from a stop state to a run state at the time of inspection input.
[0007]
In addition, when an inspection input is made, it is necessary to artificially determine that the fire has occurred, but if the fire detector detects heat using a thermistor, it is heated by a heater, etc. It takes time and inspection takes time. In addition, when the fire detection unit detects smoke, there is a problem of not only troublesome but also contamination of the detection unit when smoke is added.
[0008]
It is an object of the third and fourth inventions of the present application to obtain a fire detector that can easily perform a pseudo inspection operation.
[0009]
[Means for Solving the Problems]
In view of the above points, the present invention enters a run state upon activation input to an interrupt port, performs a fire detection operation using a fire detection unit that detects a physical quantity based on a fire phenomenon, and then enters a stop state to stop the operation. A microcomputer that enters a state, a charging circuit that is charged and discharged as an oscillation circuit, and a startup circuit that inputs a start to the interrupt port of the microcomputer when the charging voltage of the charging circuit reaches a predetermined potential, and sets the microcomputer in a run state , based on the inspection input from the outside, has a start input to the interrupt port of the microcomputer, a check detecting circuit for performing an inspection start input to the predetermined port of the microcomputer, wherein the microcomputer, to the interrupt port starting on the basis of the input performs the fire detection operation, when the time of starting the input to the interrupt port is inspected start input to the predetermined port It is characterized in that performing the check operation.
[0011]
Further, the microcomputer was used such that a fire detector for detecting a fire by measuring the discharge time corresponding to the CR time constant of the circuit connected to capacitor impedance circuit including a thermistor, said when there is inspection start input The inspection operation is performed by connecting the impedance circuit for inspection to the impedance circuit and changing the CR time constant to detect a pseudo high temperature state . In addition, the microcomputer uses a fire detection unit that activates a light-emitting circuit that emits light from the fire-detecting light-emitting element and detects a fire from the value of the light-receiving element that does not face the fire-detecting light-emitting element. When there is a start input, the inspection light-emitting element is caused to emit light simultaneously with the fire detection light-emitting element, and the inspection operation is performed from the output value of the light-receiving element at this time.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described. FIG. 1 and FIG. 2 are circuit diagrams of a thermistor type heat sensor 4h and a photoelectric smoke sensor 4s as specific examples of the fire sensor, and are used as the fire sensor 4 of the system as shown in FIG. .
[0014]
In FIG. 1, a heat sensor 4h includes a constant voltage circuit B2 that supplies a stable voltage and current, with terminals C and L to which power and signal lines 2 and 3 are connected as power sources, a resistor R1 and a capacitor C1, respectively. An oscillation circuit B5 that inputs an interrupt to the microcomputer IC1 based on the charging time constant, a heat detection circuit B4 that detects heat due to the fire based on the temperature characteristics of the thermistor TH based on the control of the microcomputer IC1, and a reset when the microcomputer IC1 runs out of control A reset circuit B3 that performs input and a switching circuit B1 that switches between terminals C and L to a substantially short-circuited state with low impedance when the microcomputer IC1 determines that a fire has occurred. Further, in order to perform an inspection operation as to whether or not the sensor is normal, an input detection circuit B6 for detecting an input from a terminal GI to which the input side which is the fire receiver side of the output line 7 is connected, and an output after the inspection operation is completed. A short circuit B7 for performing forward output of the inspection input to the terminal GO to which the output side of the line 7 is connected; a discharge circuit B8 for discharging the input to the terminal C when input from the terminal GO on the output side; Have
[0015]
Next, the operation of the heat sensor 4h will be described. In the constant oscillation circuit B5, the capacitor C1 is charged by the resistor R1, and when the charging voltage reaches a predetermined potential based on the time constant, the inverter IC4 operates to send a signal to the interrupt port INT of the microcomputer IC1. The microcomputer IC1 shifts from the stop state to the run state when an interrupt input is input to the port INT, and performs heat detection when the number of inputs to the port INT reaches a specified number (for example, 10 times). When the number of times is not the prescribed number, the microcomputer IC1 sets the port Ps to a low level (ground potential), discharges the charge of the capacitor C1, and enters a stop state as an operation stop state. Here, the stop state is a state in which the clock of the microcomputer is stopped, which is a very low consumption state of several μA, and in the run state, there is a large current consumption of several hundred μA, which is an economical state. It is.
[0016]
When heat detection is performed, the port P7 is set to a low level (ground potential) in order to discharge the charge of the capacitor C2 charged through the resistor R6 in the heat detection circuit B4 through the resistors R11 and R12 and the thermistor TH. ). At this time, the potential of the capacitor C2 is input to the port P6 of the comparator built in the microcomputer IC1 through the resistor R10 and monitored, and the microcomputer IC1 measures the temperature by measuring the discharge time. The reference potential of the comparator built in the microcomputer IC1 is determined by the resistors R7 and R8. Although not shown, the thermistor TH is provided so as to protrude from the sensor body and responds to the ambient temperature at the location where the sensor is installed. The discharge time from the capacitor C2 through the thermistor TH depends on the temperature. The temperature can be detected by this discharge time. Further, every time the heat detection operation is performed, instead of setting the port P7 to the low level, the port P8 is set to the low level, so that the charge discharge of the capacitor C2 is discharged only by the resistor R11, and the discharge is not affected by the temperature. Measure time. Then, by detecting the temperature by taking the ratio of the discharge time including the thermistor TH and the discharge time not including it, temperature measurement can be performed while eliminating variations due to individual differences of the capacitor C2.
[0017]
When the microcomputer IC1 determines that a fire has occurred based on the measurement result in accordance with a discrimination criterion (such as a constant temperature discrimination temperature or a differential discrimination temperature increase) set in advance in the storage means or the like, the port Pf Is set to the high level, the transistor Q4 of the switching circuit B1 is turned on to switch between the terminals C and L, and at the same time, the transistor Q3 is turned on to light the confirmation lamp by the light emitting diode LED. The terminal C and L have a polarity so that the terminal C side becomes a ground potential in relation to the inspection function described later, and the diode D1 prevents the influence due to the reverse connection to the power supply / signal lines 2 and 3. is doing.
[0018]
At the time of inspection, a voltage is applied to the thermal sensor 4h via the output line 7 to the terminal GI, which is used as an inspection input. The transistor Q5 of the input detection circuit B6 is turned on by the voltage at the terminal GI, and a signal is sent to the interrupt port INT of the microcomputer IC1 when the transistor Q1 is turned on. The input to the interrupt port INT is shared with the input from the oscillation circuit B5 via the dual diode D2, and whether or not the input is from the input detection circuit B6 depends on the input level to the port P1 where the input is performed simultaneously. Can be distinguished by the high level. That is, the microcomputer IC1 detects that the input level to the port P1 is high when an interrupt input is input to the port INT and shifts from the stop state to the run state, and the interrupt input from the input detection circuit B6 is detected. The inspection operation is started.
[0019]
Since the inspection input to the terminal GI via the output line 7 is not always received when the microcomputer IC1 is in the stop state, the level of the port P1 is confirmed at a predetermined timing when the microcomputer IC1 is in the run state. Even during the heat detection operation, the inspection operation is preferentially performed by detecting the high level of the port P1. This is because it is necessary to output an inspection signal at a predetermined timing in the above-described system inspection operation.
[0020]
In the inspection operation by the microcomputer IC1, in order to charge the capacitor C2 to a predetermined potential at an early stage, the port P5 is set to the high level and charged with the resistor R6 and a resistor R9 smaller than this. Then, in order to form a pseudo high temperature state, the port P7 and the port Pt are simultaneously set to a low level and discharged from the capacitor C2. At this time, by connecting the resistor Rt in parallel to the thermistor TH or the like, the discharge time constant is changed and the discharge time is shortened, and the microcomputer IC1 detects the high temperature state in a pseudo manner via the port P6. It will be. Based on the result, the microcomputer IC1 determines that a fire has occurred and sets the port Pf to high level to turn on the transistor Q4 of the switching circuit B1 to switch between the terminals C and L. At the same time, the transistor Q3 is switched on. Turns on and turns on the confirmation lamp by the light emitting diode LED. The timing of the switching operation is performed at a predetermined timing in accordance with the inspection operation of the system described later, and an inspection signal is output from the terminals C and L. Thus, by changing the discharge time constant based on the inspection input, it is possible to detect a pseudo high temperature, and the inspection operation can be easily performed. At this time, the microcomputer IC1 stores the inspection result in a built-in storage means not shown in detail.
[0021]
After the inspection output, the microcomputer IC1 performs a forward operation so that the inspection input from the receiving unit to the next sensor can be performed. At this time, the discharge operation of the discharge circuit B8, which will be described later, is stopped. Therefore, the port P3 is set to the high level, the port P2 is set to the high level, the transistor Q7 of the short circuit B7 is turned on, the transistor Q6 is turned on, and the terminals GI and GO are short-circuited. As a result, the inspection input voltage of the output line 7 input to the terminal GI flows to the next sensor through the terminal GO, and the next sensor performs the inspection operation in the same manner as described above. Then, after this operation, the microcomputer IC1 continues the run state because the voltage continues at the terminal GI, and performs the normal operation of monitoring the fire while monitoring the input state of the terminal GI. At this time, the current consumption of the entire system in FIG. 4 increases, but there is no problem because the inspection operation is temporary.
[0022]
The terminals GI and GO to which the output line 7 is connected have polarity. If the output line 7 is connected in reverse, the internal parts may be defective. Therefore, when there is an input from the terminal GO, the discharge circuit B8 is provided between the terminal GO and the terminal C in order to discharge the input to the common line 2 which becomes the ground potential and protect the internal components. That is, when there is an input from the terminal GO, the transistors Q9 and Q10 are turned on before the transistor Q6 of the short circuit B7 and discharged to the terminal C through the resistor R33 having a small resistance value.
[0023]
In the inspection operation of the system to be described later, the inspection device 12 in FIG. 4 applies a voltage from the terminal G to the output line 7 and outputs a pulse, but the output line 7 is erroneously connected to each sensor 4 in reverse. If there is something, it becomes a potential indicating an erroneous connection by the resistor R33 based on the operation of the emission circuit B8. As a result, the inspector 12 detects the potential by detecting the potential, and can also detect the sensor that has been normally inspected, so it can also determine the number of the erroneously connected sensor. .
[0024]
In addition, if this discharge circuit B8 is activated during the above-described forward operation in the sensor, even if the terminals GI and GO are short-circuited, the inspection input is discharged to the terminal C and can be sent to the next sensor. Can not. Therefore, at the time of the above-described forward operation, the port P3 is set to the high level to turn on the transistor Q8 of the emission circuit B8 so that no operating voltage is applied to the transistor Q9.
[0025]
Here, the microcomputer IC1 performs a fire detection operation using the heat detection circuit B4 for detecting heat due to a fire based on the temperature characteristics of the thermistor TH in the run state, and then enters a stop state as an operation stop state. The resistor R1 and the capacitor C1 of the oscillation circuit B5 are an example of a charging circuit, and the inverter IC4 is an example of a starting circuit.
[0026]
Further, the transistor Q5 and the transistor Q1 of the input detection circuit B6 are an example of an inspection detection circuit, and the microcomputer IC1 performs a fire detection operation based on an input to the port INT, and simultaneously performs an inspection operation when there is an input to the port P1. It is an example of the control circuit which performs.
[0027]
Further, the microcomputer IC1 is an example of a control circuit that detects heat from an impedance circuit including resistors R11 and R12 including a thermistor TH as a fire detection element and a capacitor C2. The transistor Q5 and the transistor Q1 of the input detection circuit B6 are: It is an example of an inspection detection circuit, and the resistor Rt is an example of an impedance circuit for inspection.
[0028]
In FIG. 2, the smoke detector 4s, like the heat detector 4h, has terminals C and L to which the power and signal lines 2 and 3 are connected, a constant voltage circuit B2, an oscillation circuit B5, and a reset circuit B3. , A switching circuit B1, an input detection circuit B6, a short circuit B7, and a discharge circuit B8. Further, instead of the heat detection circuit B4 as the fire detection circuit, the light scattered by the smoke in the smoke detection unit that blocks outside light (not shown) is received based on the light emission of the light emitting diode Ls as the light emitting element based on the control of the microcomputer IC5. It has a light emitting circuit B14, an amplifier circuit B11, and a sample hold circuit B12 for detecting smoke due to a fire by the output of a photodiode PD as a light receiving element.
[0029]
Next, the operation of the smoke detector 4s will be described. Similarly to the microcomputer IC1 of the heat sensor 4h, the microcomputer IC5 shifts from the stop state to the run state when an interrupt input is constantly input to the port INT based on the oscillation circuit B5, and the number of inputs to the port INT is the specified number of times. Detect smoke when it reaches. The voltage between the capacitor C1 and the resistor R1 of the oscillation circuit B5 starts to be charged to the capacitor C1 through the resistor R1 from the same state as the power supply, and the potential is lowered. When this potential decreases to the port threshold voltage of the AND gate IC6, the output of the AND gate IC6 to the port INT of the microcomputer IC5 changes from high level to low level. The microcomputer IC5 detects a low level input to the port INT.
[0030]
When performing smoke detection, the microcomputer IC5 sets the port P7 to high level and causes the light emitting diode Ls to emit light in order to discharge the charge of the capacitor C3 charged through the resistor R26 in the light emitting circuit B14. The light reception output of the photodiode PD at this time is input to the port P6 of the comparator built in the microcomputer IC5 through the amplifier circuit B11 and the sample hold circuit B12.
[0031]
Then, the microcomputer IC5 switches between the terminals C and L by the switching circuit B1 when the port Pf is set to the high level when it is determined that the fire is based on the measurement result in accordance with the determination criterion set in the storage means or the like in advance. At the same time, the confirmation LED is turned on.
[0032]
At the time of inspection, a voltage is applied as an inspection input to the terminal GI via the output line 7 to the smoke detector 4s. The transistor Q5 of the input detection circuit B6 is turned on by the voltage of the terminal GI, and accordingly, the input of the AND gate IC6 is made low and a low level signal is sent to the interrupt port INT of the microcomputer IC5. The input to the interrupt port INT is different from the method used in common with the oscillation circuit B5 via the dual diode D2 of the heat sensor 4h, but the potential is low level by charging the capacitor C1 of the oscillation circuit B5 described above. Then, the input of the AND gate IC6 becomes low and a signal is sent to the interrupt port INT of the microcomputer IC5 to perform the same operation. Whether or not the input is from the input detection circuit B6 can be distinguished from the fact that the input level to the port P1 of the microcomputer IC5 to which the input is simultaneously performed is a low level. That is, the microcomputer IC5 detects that the input level to the port P1 is low, determines that the input is an interrupt input from the input detection circuit B6, and starts the inspection operation, like the heat detector 4h. .
[0033]
In the operation of checking the smoke detector 4s by the microcomputer IC5, in order to charge the capacitor C3 at an early stage, the port P5 is set to the high level and the resistor R26 is connected in parallel with the resistor R26. Then, the port P7 and the port Pt are simultaneously set to the high level, and the inspection light emitting diode Lt is caused to emit light together with the light emitting diode Ls. The light-emitting diode Lt for inspection allows light to be directly input to the photodiode PD due to the arrangement in the smoke detection unit (not shown), and the output of the photodiode PD becomes large even if no smoke is present, and the port P6 The microcomputer IC5 detects smoke with a high concentration in a pseudo manner. Based on the result, the microcomputer IC6 determines that a fire has occurred, sets the port Pf to the high level, switches between the terminals C and L by the switching circuit B1, and turns on the confirmation lamp by the light emitting diode LED. As with the heat detector 4h, the timing of this switching operation is to output an inspection signal at a predetermined timing in accordance with the inspection operation of the system described later. At this time, the microcomputer IC5 stores the inspection result in a built-in storage means not shown in detail.
[0034]
After this inspection output, the microcomputer IC5 performs the forward operation so that the inspection input to the next sensor from the receiving unit side can be performed by the short circuit B7, similarly to the heat sensor 4h, and the terminal GI and the terminal GO To short circuit. After this operation, the microcomputer IC5 continues the run state, and performs a normal operation for monitoring the fire while monitoring the input state of the terminal GI. Further, if the discharge circuit B8 is activated during the forward feed operation, the inspection input is discharged to the terminal C even if an attempt is made to short-circuit between the terminals GI and GO. Therefore, during the forward feed operation, the port P3 is set to the high level and the transistor of the discharge circuit B8. It is necessary to turn on Q8 so that the operating voltage is not applied to the transistor Q9. Here, a Zener diode Z1 is provided in series with the transistor Q8 of the emission circuit B8 instead of the resistor R33 of FIG.
[0035]
Here, the microcomputer IC5 outputs the photodiode PD as the light receiving element that receives the scattered light by the smoke in the smoke detection unit that blocks outside light (not shown) based on the light emission of the light emitting diode Ls as the light emitting element in the run state. Is an example of a control circuit that performs a fire detection operation using the light emitting circuit B14, the amplification circuit B11, and the sample hold circuit B12 for detecting smoke due to fire, and then enters a stop state as an operation stop state. The resistor R1 and the capacitor C1 are an example of a charging circuit, and the AND gate IC6 is an example of a starting circuit.
[0036]
The transistor Q5 of the input detection circuit B6 is an example of an inspection detection circuit. The microcomputer IC5 performs a fire detection operation based on an input to the port INT, and simultaneously performs an inspection operation when there is a low input to the port P1. It is an example of a control circuit.
[0037]
Further, the microcomputer IC5 causes a fire by the output of the photodiode PD as a light receiving element that receives the scattered light by the smoke in the smoke detecting section that blocks outside light (not shown) based on the light emission of the light emitting diode Ls as the light emitting element for fire detection. It is an example of a control circuit that performs a fire detection operation using the light emitting circuit B14, the amplifier circuit B11, and the sample hold circuit B12 for detecting smoke, and the transistor Q5 of the input detection circuit B6 is an example of an inspection detection circuit, The light emitting diode Lt is an example of an inspection light emitting element.
[0038]
Although the thermistor type thermal sensor 4h and the photoelectric type smoke sensor 4s as specific examples of the fire sensor 4 used in the system of FIG. 4 as described above have been described, other types such as a flame sensor, The odor detector or the like can be used with a circuit configuration as shown in FIG. Here, the control circuit Bc corresponds to the microcomputer IC1 in FIG. 1 and the microcomputer IC5 in FIG. 2, and the fire detection circuit Bf includes the heat detection circuit B4 in FIG. 1, the light emission circuit B14 in FIG. 2, the amplification circuit B11, and the sample hold. Corresponding to the circuit B12, the input circuit Bi corresponds to the AND gate IC6 of FIG. 2, such as the dual diode D2 of FIG. The input circuit Bi is an interrupt input to the microcomputer serving as the control circuit Bc and an inspection input at the time of input of the input detection circuit B6 by the input from the oscillation circuit B5 or the input detection circuit B6. When configuring other types of detectors, the fire detection circuit Bf may be matched to the detection target. For example, in the case of a flame detector, a fire detection circuit using a pyroelectric element or a UV lamp, an odor detection In the case of a vessel, a fire detection circuit using a semiconductor element such as stannic oxide or a crystal resonator may be used.
[0039]
Hereinafter, the entire system of FIG. 4 in which the above-described heat sensor 4h and smoke sensor 4s are used will be described.
[0040]
In FIG. 4, for example, a plurality of fire detectors 4 provided in each room or the like on a power / signal line composed of a common line 2 and a line 3 drawn from a fire receiver 1 provided in a living room (not shown). Are connected in parallel by a feed wiring, and a terminating resistor 5 is connected to the rear ends of the signal lines 2 and 3.
[0041]
Further, between the fire receiver 1 of the signal lines 2 and 3 and each fire detector 4, a line switch 6 that always switches and connects the common line 2 and the line line 3 to the fire receiver 1 is disposed. Has been. An output line 7 is provided from the line switching unit 6 for performing inspection input to each fire detector 4. The output line 7 is wired so that it can be forwarded to each fire detector 4 as described above, and the rear end of the fire sensor 4 is connected to the common line 2 via the termination diode 8. This output line 7 is normally in a no-voltage state without being supplied with an inspection input. An inspection output line 9 is wired from the line switch 6 to the fire receiver 1 side.
[0042]
At each time, each fire detector 4 performs the above-described fire monitoring with the power supplied from the fire receiver 1 through the signal lines 2 and 3, and performs a switching operation when a fire is detected to connect between the signal lines 2 and 3. Set to a substantially short-circuited state. The fire receiver 1 detects a substantially short-circuit state based on the switching operation and performs a fire notification operation. At this time, for example, the fire receiver 1 displays a fire on the outdoor display 10 provided and connected to the entrance, or is not a dwelling unit complete type. When necessary, it outputs the necessary fire signal. At the time of inspection, the inspection device 12 is connected to the connector 11 drawn out from the line switching device 6 to the outdoor display 10 side, for example. Based on the inspection operation from the inspection device 12, the line switching unit 6 outputs an inspection start output to the fire receiver 1 via the inspection output line 9, and displays that the inspection is in progress to the fire receiver 1. The signal lines 2 and 3 to the sensor 4 are disconnected from the fire receiver 1 and connected to the inspection device 12. In this state, the fire receiver 1 performs an inspection display based on the inspection start output of the line switching device 6 and enables an outdoor inspection from the inspection device 12. At this time, each fire detector 4 is operated by the power supplied from the inspection device 12 through the signal lines 2 and 3.
[0043]
There are three inspection modes from this inspector 12, and an external test is conducted without entering the room, and an outdoor inspection mode for judging the quality of the entire system and an abnormality in the inspection mode are entered. It has a sensor specific mode for specifying the location of the abnormal fire sensor, and a sensor designation mode for checking only a specific sensor.
[0044]
FIG. 5 shows the terminal G output of the inspection device 12 to the output line 7, the terminal GI input of each fire detector 4 from the output line 7, and the signal in the outdoor inspection mode when n fire detectors 4 are connected. It is a signal waveform detected between the terminals C and L of the inspection device 12 by the lines 2 and 3. The checker 12 applies a voltage as a check input from the terminal G to the output line 7 and outputs, for example, pulses A, B, and C having a width of 5 mS at the timing shown in FIG.
[0045]
Between the terminals GI and GO of each fire detector 4 is always open as described above, and the first detector in the waveform of FIG. 5 has its built-in microcomputers IC1 and IC5 raised by voltage application to the terminal GI, The inspection operation is started at the falling edge of the pulse A1. In this inspection operation, if the sensor is a photoelectric smoke detector 4s, light is emitted at intervals of about 3 seconds during normal fire monitoring, and fire is detected with three consecutive detections. Inspection is performed by detection once based on the light emission of the light emitting diode Lt. In the case of the thermistor type heat sensor 4h, inspection is performed by connecting a fixed resistor Rt in parallel to the thermistor TH. Furthermore, even in a heat sensor using a bimetal or an air chamber, the contact mechanism is made to perform a closing operation, and each of them is inspected by a pseudo input method. Here, the interval TW1 between the pulse A and the pulse B in FIG. 6 is a time sufficient for each fire detector 4 to perform an inspection operation, for example, 0.5 seconds.
[0046]
If the inspection result is normal, the first sensor switches between the terminals C and L from the fall of the pulse B1 to the fall of the pulse C1. The waveform of the signal appears as a pulse in the waveform between the terminals C and L of the inspection device 12 in FIG. The corresponding interval TW2 between the pulse B and the pulse C in FIG. 6 may be a time that can be detected as an inspection signal for operation confirmation by the inspection device 12, and is, for example, 20 mS. Then, the terminals GI and GO are short-circuited when the falling of the pulse C1 in FIG. 5 is detected. As a result, after the transmission of the pulse C1, the voltage is applied as the inspection input to the terminal GI of the second sensor. Built-in microcomputers IC1 and IC5 start up. A corresponding interval TW3 between the pulse C and the next pulse A in FIG. 6 is sufficient for the microcomputers IC1 and IC5 to rise, for example, 30 mS.
[0047]
Then, the second sensor starts an inspection operation by the fall of the pulse A2 in FIG. 5. At this time, the first sensor performs a normal fire monitoring operation simultaneously with a short circuit between the terminals GI and GO. Continuing, a pulse is detected from the terminal GI simultaneously with the second sensor, but no inspection operation is performed. After the inspection of the final n-th sensor, the output line 7 is connected to the common line 2 via the termination diode 8, and the inspection device 12 detects the current flowing through the termination diode 8 and And the output of the terminal G is stopped. In each sensor 4, when the inspection input to the terminal GI is stopped, the transistor Q5 of the input detection circuit B6 is turned off, the port P2 of the microcomputers IC1 and IC5 is set to low level, and the transistors Q6 and Q7 of the short circuit B7 are turned on. Turns off and opens between terminals GI and GO to return to the normal monitoring state.
[0048]
In this way, in the outdoor inspection mode, the inspection input signal is sent to the terminal GI of each sensor 4 using the output line 7 and the terminals GI and GO are short-circuited after the inspection operation, so that the inspection operation can be surely performed forward. By detecting the inspection signal based on the inspection result as a pulse between the terminals C and L of the inspector 12 up to the nth sensor, the number of sensors that have been inspected normally and the number of abnormal detectors are detected. You can figure out what number. In addition, the detectors connected to the same signal lines 2 and 3 that are not being inspected continue to monitor the fire with the power supplied from the inspector 12 supplied through the power and signal lines 2 and 3 and detect the fire. The detected sensor emits a normal fire signal. The inspector 12 determines a fire by detecting a signal that is not synchronized with the interval TW2 between the pulses B and C in FIG.
[0049]
Next, the detector specifying mode for specifying the location of the abnormal fire detector when there is an abnormality in the outdoor inspection mode will be described. The waveforms at this time are shown in FIGS. 7 and 8 as in FIGS.
[0050]
Between the terminals GI and GO of each fire detector 4 is after the outdoor inspection mode is finished, and since the inspection input voltage is not output from the inspection device 12, it is open. When the inspection device 12 is switched from the outdoor inspection mode to the detector identification mode, the pulse G shown in FIG. As for the sensor, the built-in microcomputer rises when a voltage, which is an inspection input to the terminal GI, is applied, and starts an inspection operation when the pulse A1 in FIG. 7 falls. Then, as shown in FIG. 8, the interval TW4 between the pulse A and the pulse B in the sensor specifying mode is, for example, 20 mS, and the pulse B is immediately transmitted unlike the outdoor inspection mode. By detecting the pulse B at a short timing, the sensor interrupts the inspection operation, and from the inspection result in the outdoor inspection mode immediately before being stored in the microcomputers IC1 and IC5, if it is not abnormal, the detector detects the pulse C from the falling edge of the pulse B. Turn on the confirmation lamp until the fall of. The operation time TW5 is a time during which the confirmation lamp can be visually confirmed sufficiently to identify the sensor in the room, for example, 0.5 seconds. As in the outdoor inspection mode, when the falling edge of the pulse C1 is detected, the first sensor short-circuits between the terminals GI and GO, and a voltage is applied as an inspection input to the terminal GI of the next sensor. Similarly, a built-in microcomputer starts up. The interval TW3 between the pulse C and the next pulse A is the same as described above.
[0051]
As described above, in the detector specifying mode, each fire detector 4 is caused to turn on the confirmation lamp based on the inspection result up to the nth detector using the result of the previous outdoor inspection mode. That is, even if the presence or number of an abnormal detector is known in the outdoor inspection mode, the position cannot be specified specifically, and even if there is detailed equipment data, the actual wiring may be different. Therefore, according to the sensor identification mode, it can be visually confirmed that a normal sensor is lit and an abnormal sensor is not lit, which is an effective means for confirming the specific position of the abnormal sensor. In addition, as in the outdoor inspection mode, it goes without saying that the sensors other than those under inspection continue the fire monitoring.
[0052]
Next, a detector designation mode for confirming the location of the specified abnormal fire detector will be described. The waveforms at this time are shown in FIG. 9 and FIG. 10 as in FIG. 5 and FIG. 6 or FIG. 7 and FIG. In this mode, the inspection device 12 specifies the number of the sensor to be checked (second in FIG. 7), and the inspection device 12 applies a voltage from the terminal G only to the sensor specified for the output line 7. Then, pulse output is performed at the same timing as in FIG. 8, and the interval TW6 between the pulse B and the pulse C is shortened to 20 mS, for example, as shown in FIG. 10 for other sensors.
[0053]
Between the terminals GI and GO of each fire detector 4 is after the outdoor inspection mode is finished, and since the inspection input voltage is not output from the inspection device 12, it is open. When switching from the outdoor inspection mode to the detector specifying mode, pulses A1 to Cn having a pulse width of 5 mS as shown in FIG. The built-in microcomputer rises when the voltage is applied to the terminal GI, and the detector starts an inspection operation when the pulse A falls. Then, the pulse B is immediately transmitted, the check operation is interrupted, and the check light is turned on from the fall of the pulse B to the fall of the pulse C if normal, based on the check result of the previous outdoor check mode. With respect to this operation time, the interval between the pulses B2 and C2 for the second sensor shown in FIG. 9 is an interval TW5 at which the confirmation lamp can visually confirm sufficiently to identify the sensor in the room. For the sensors other than the second sensor (first or n-th sensor), a pulse is output from the checker 12 at the timing interval TW6 shown in FIG.
[0054]
As described above, in the detector designation mode, as in the sensor identification mode, the fire lights 4 are turned on based on the inspection results up to the nth sensor using the result of the outdoor inspection mode. However, only the sensor that is expected to be abnormal is turned on for a sufficient time, and the other sensors are shortened. In other words, the position of the abnormal sensor can be specifically identified in the sensor identification mode and confirmed. Therefore, the sensor designation mode is an effective means for confirming that the sensor is an abnormal sensor. In addition, as in other modes, it goes without saying that sensors other than those under inspection continue to monitor fire.
[0055]
As described above, in this embodiment , the control enters the run state by the activation input to the interrupt port INT, performs the fire detection operation using the fire detection unit that detects the physical quantity based on the fire phenomenon, and then enters the operation stop state. The microcomputer IC1 and IC5 as the circuits, the oscillation circuit B5 as the charging circuit to be charged / discharged , and the charging voltage to the capacitor C1 of the oscillation circuit B5 are input to the interrupt port INT of the microcomputer IC1 etc. Inverter IC4 or AND gate IC6 serving as a start circuit for bringing microcomputer IC1 or the like into a run state, and start input and check start input to interrupt port INT and predetermined port P1 of microcomputer IC1 and IC5 based on an external check input An inspection detection circuit B6 to be performed, and the microcomputers IC1 and IC5 have the start input Since the fire detection operation is performed based on the start input and the inspection start input, the inspection operation is performed. Therefore, the microcomputer IC1 and IC5 stop state is used to charge the capacitor C1 and other circuits. It is possible to stop the fire detector with low current consumption, and even if the microcomputer IC1 and IC5 are in the stop state, the microcomputer IC1, The inspection operation can be performed when the IC 5 has an inspection start input together with a start input.
[0057]
Furthermore, a control circuit that performs a fire detection operation using a fire detection unit that detects a fire by measuring a discharge time corresponding to a CR time constant of a circuit in which a capacitor C2 is connected to an impedance circuit including a thermistor TH as a fire detection element A microcomputer IC1 and an inspection detection circuit B6 for inputting an inspection start input to the microcomputer IC1 based on an inspection input from the outside. The microcomputer IC1 has an inspection resistor in the impedance circuit when the inspection start input is present. Since the inspection operation is performed by connecting the impedance circuit for inspection by Rt and detecting the pseudo high temperature state by changing the CR time constant , the pseudo fire discrimination can be easily performed.
[0058]
In addition, the light-emitting circuit B14 that emits light from the light-emitting diode Ls as the fire-detecting light-emitting element is activated, and fire detection is performed to detect a fire from the value of the output of the photodiode PD as the light-receiving element that does not face the light-emitting element for fire detection A microcomputer IC5 serving as a control circuit for performing a fire detection operation using the control unit, and an inspection detection circuit B6 for performing an inspection start input to the microcomputer IC5 based on an inspection input from the outside, and the microcomputer IC5 starts the inspection When there is an input, the light emitting diode Lt as the inspection light emitting element facing the photodiode PD is caused to emit light simultaneously with the light emitting diode Ls, and the inspection operation is performed from the value by the output of the photodiode PD at this time. Fire discrimination can be performed easily.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a thermistor type heat detector as a specific example of a fire detector.
FIG. 2 is a circuit diagram of a photoelectric smoke detector as a specific example of a fire detector similar to FIG.
FIG. 3 is a block circuit diagram showing a configuration necessary as a fire detector.
FIG. 4 is a schematic configuration diagram of a system in which each fire detector can be used.
FIG. 5 is a signal waveform diagram in the outdoor inspection mode of FIG. 4;
6 is a signal waveform diagram showing the timing of the pulses in FIG. 5. FIG.
7 is a signal waveform diagram in the sensor specific mode of FIG. 4;
8 is a signal waveform diagram showing the timing of the pulses in FIG.
9 is a signal waveform diagram in the sensor designation mode of FIG. 4;
10 is a signal waveform diagram showing the timing of the pulses in FIG. 9. FIG.
[Explanation of symbols]
IC1, IC5 Control circuit IC4, IC6 Start-up circuit B5 Charging circuit B6 Inspection detection circuit

Claims (3)

Becomes run state at the start input to the interrupt port, and performs fire detection operation using a fire detection unit that detects a physical quantity based on a fire phenomenon, the operation stop state thereafter a stop state microcomputer,
A charging circuit that is charged and discharged as an oscillation circuit ;
When the charging voltage of the charging circuit reaches a predetermined potential, a startup input is performed to the microcomputer interrupt port, and the microcomputer is in a run state;
Based on an inspection input from the outside, having an activation input to the interrupt port of the microcomputer, and an inspection detection circuit for performing an inspection start input to a predetermined port of the microcomputer ,
The microcomputer fire based on said start input to the interrupt port performs the fire detection operation, when the time of starting the input to the interrupt port is inspected start input to the predetermined port and performing an inspection operation sensor. The microcomputer uses a fire detection unit that measures the temperature by measuring the discharge time according to the CR time constant of the circuit where the capacitor is connected to the impedance circuit including the thermistor , and has an inspection start input. 2. The fire detector according to claim 1, wherein an inspection operation is performed by connecting an impedance circuit for inspection to the impedance circuit and detecting a pseudo high temperature state by changing the CR time constant. The microcomputer starts a light-emitting circuit that emits light from the fire-detecting light-emitting element, and uses a fire detection unit that detects a fire from the value of the light-receiving element not facing the fire-detecting light-emitting element. 2. The fire detector according to claim 1, wherein when there is a light, the inspection light emitting element is caused to emit light simultaneously with the fire detecting light emitting element, and the inspection operation is performed from the output value of the light receiving element at this time.

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