JP4702305B2 - Fire alarm - Google Patents

Description

The present invention, smoke, upon detecting a fire factors such as heat relates fire alarm for informing fire, details regarding the improvement of the fire alarm device having an operation test function.

  Conventionally, this type of fire alarm has been subjected to an operation test by actually generating a fire factor such as smoke or heat and causing the fire detection means to detect it. However, until the fire alarm actually detects the fire factor, it requires a lot of smoke and a rise in the heat temperature, so it took a considerable time for the operation test.

Therefore, in Patent Document 1 below, in order to solve the above problem, in the smoke detector, the set time value corresponding to all the smoke detectors is set to zero or a short time close to zero in the detector inspection mode. The thing provided with the inspection fire judgment means judged to be a fire by the value and the detected smoke density is disclosed. This is because the set time for detecting smoke is set to a short time in the inspection mode, and a fire determination is inevitably performed in a state where the detection level of the detected smoke concentration is lowered. Although the fire determination is not performed by switching the concentration to a level lower than that at the time of fire monitoring, it is said that the fire occurrence determination time can be shortened.
Public Utility Sho 61-46692

However, in the above smoke detector, after the operation test (inspection) is completed, the original setting time is not set unless the setting time in the inspection mode is reset from the setting time in the inspection mode. It was.
In other words, except during the operation test, if the set time for fire monitoring is not reached, the actual fire judgment operation cannot be performed properly, but the set time after the operation test is set to the set time for fire monitoring. If you forget to return it, it will cause a false alarm, which is a problem because it impairs the reliability of the fire alarm. In addition, since such a fire alarm is normally installed on the ceiling, it is very troublesome to operate a button or the like for returning from the inspection mode to the normal fire monitoring state.

  Therefore, the present invention has been proposed in view of the above circumstances, and an object thereof is to provide a fire alarm that can perform an operation test quickly and has high reliability.

It is determined whether a fire detection means that detects a fire factor such as smoke or heat and outputs a detection signal, and whether or not the detection signal output from the fire detection means exceeds a set reference level. A fire detection signal is output when it exceeds the limit, and the number of times the above fire detection signal is output is counted every predetermined time. A fire alarm device having an alarm determination circuit that outputs a reference signal of the alarm determination circuit until a predetermined time elapses when the test signal is received. while switching and setting the level to a lower level than the original reference level, after a predetermined time has elapsed, Rutotomoni comprises a mode switching means for returning to the original reference level, the onset report discrimination circuit, the Fire detection means It is equipped with a test discriminating means consisting of a discriminating circuit that performs an internal circuit test for discriminating the presence or absence of disconnection and short-circuiting, and a discriminating circuit that performs an overburst test operation. During the internal circuit test and the overburst test, a reference level for fire monitoring Lower than each other and different reference levels are set, and the alarm determination circuit sets the count value to a value smaller than that at the time of fire monitoring until the timer passes the predetermined time. At the same time, the reference level is set to the reference level for the internal circuit test or the reference level for the blow test .
Therefore, by inputting a test signal, it is possible to perform an operation test of fire alarm such as a blink test at a level lower than that at the time of fire monitoring.

According to a second aspect of the present invention, the fire alarm device includes a control contact for supplying the detection signal from the fire detection means to the two determination circuits when the mode switching means receives the test signal. Yes.

According to the fire alarm device described in claim 1, the reference level of the alarm determination circuit is set to a level lower than the original reference level until a predetermined time elapses after the timer is started. On the other hand, there is mode switching means to return to the original reference level after a predetermined time has passed, so the amount of smoke and heat temperature are low compared to the actual fire judgment at the time of fire monitoring A fire is detected underneath and an operation test can be performed in a short time. Thus, for example, even when employed as a fire alarm installed in a relatively large facility, the time required for the operation test can be shortened.
In addition, since the configuration is such that the original reference level is automatically restored after the predetermined time has elapsed, it is necessary for the operator to perform a setting operation to return the reference level to the original reference level after the operation test. There is no time and effort. Therefore, it is possible to prevent the reference level from being kept at a low level during fire monitoring, and it is possible to configure a highly reliable fire alarm device.
Furthermore, since the reference level when switched to a lower level is higher than the normal output level range during the normal operation test, there is no problem that a warning test or the like is not performed.

Further , according to the fire alarm device described in claim 1 , the fire alarm determination circuit sets the count value to a value smaller than that at the time of fire monitoring until a predetermined time elapses. Since the reference level is set to a level lower than the original reference level, an operation test can be performed quickly. In other words, according to this, by setting the count value to a smaller value in addition to the point at which the fire is detected when the detected temperature is lower than the actual fire judgment at the time of fire monitoring, the detected temperature at the reference level can be reduced. The operation test can be performed more quickly at a low level both by lowering and lowering the count value.

Furthermore , according to the fire alarm device described in claim 1 , the fire detector is constituted by a determination circuit for performing an internal circuit test for determining whether or not the fire detection means is disconnected or short-circuited, and a determination circuit for performing a flash test operation. Because it is equipped with a test discriminating means, it is possible to perform a test for the presence or absence of a disconnection or short circuit that makes it difficult to detect abnormalities with only the so-called spot test. It can be performed.

According to the fire alarm device described in claim 2 , since the mode switching means is provided with a control contact for switching the detection signal from the fire detection means to the two discrimination circuits upon receiving the test signal. In addition, it is possible to switch between the operation test and the fire monitoring, and to improve the reliability as a fire alarm.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing an example of the main configuration of the fire alarm of the present invention, FIG. 2 is a diagram showing an example of the circuit configuration of the block diagram shown in FIG. 1, and FIG. It is a figure which shows the relationship between the reference level of a test report and a fire report. This section describes a fire alarm that can perform not only a fire alarm test but also an internal circuit test for whether the sensor outputs a normal range in a normal monitoring state. However, it goes without saying that it can also be applied to a fire alarm that performs only a blow test. In the following description, a predetermined voltage level set in advance for detecting disconnection or short-circuiting is defined as voltage level EH, EL, and a voltage level that is switched during a blow test to perform a fire alarm test is defined as a reference level EB. The voltage level during fire monitoring is the reference level EA.

  In the figure, 1 is a fire alarm device 1 having an operation test function, 10 is a fire detection means for outputting a detection signal corresponding to the ambient temperature by a temperature sensor 10a composed of a thermistor, and 11 is a fire detection means 10. Fire detection discriminating means for outputting a fire detection signal when the detection signal output from the signal exceeds a set reference level, 12 discriminates various signals output from the fire alarm discriminating means 11 or the test discrimination means 13 A fire alarm processing means for outputting a predetermined alarm signal, 13 a test discriminating means for performing an operation test upon receiving a test signal and outputting a normal operation discriminating signal, and a timer 14b for measuring a preset predetermined time. A mode switching means for setting a reference level of a later-described alarm determination circuit 15 to be switchable between upper and lower two stages; 15 is a fire alarm determination means 11 and a fire alarm processing means 12; It is composed onset report discrimination circuit in a test determining means 13.

  The fire alarm unit 12 includes a counter 12a. The counter 12a determines the output duration time of various signals sent from the fire alarm discriminator 11 and the test discriminator 13, that is, the fire detection signal or the normal operation discrimination signal. Counting is performed every predetermined time, and when a predetermined count value is reached, it is determined whether it is an actual fire or an operation test, and a predetermined alarm signal is output according to the determination result.

The mode switching means 14 includes a timer 14b, a relay switching unit 14a, and a first switch S1 and a second switch S2 that serve as control contacts. The relay switching unit 14a receives a test signal and enters a test mode. When the switching is set, the first switch S1 is closed until a predetermined time elapses. When the predetermined time elapses, the first switch S1 is opened and the second switch S2 is closed. Here, the test signal may adopt various modes such as a configuration in which a test button (not shown) provided in the fire alarm device 1 is manually operated and a configuration in which the test signal is input by remote control using a remote controller or the like. it can.
In the figure, the timer 14b is built in the relay switching unit 14a, but it goes without saying that it may be provided separately.

  In the fire alarm discrimination means 11, one reference level EA is set for discriminating an actual fire, and in the test discrimination means 13, two different voltage levels are used for discriminating disconnection and short-circuit abnormality of the fire detection means 10. EH and EL are set. Further, in the test discriminating means 13, a reference level EB which is a reference level at the time of the fog test by the fire detecting means 10 is set, and when the test signal is received, the mode switching means 14 switches the reference level from EA to EB. It is configured to perform a head test.

  In the operation test, the test discriminating unit 13 first performs an internal circuit test to determine whether the temperature sensor 10a of the fire detection unit 10 outputs a normal range in a normal state within a predetermined time. It is configured to perform a test to see if the fire alarm is properly performed. Here, the configuration in which the operation test is performed after the internal circuit test is performed will be described. However, the present invention is not limited thereto, and the internal circuit test may be performed after the operation test.

FIG. 2 is a diagram showing an example of the circuit configuration of the block diagram shown in FIG.
The alert determination circuit 15 is configured by combining at least two determination circuits having different reference levels. In FIG. 2, the determination circuit 15 further includes a determination circuit having a different voltage level for determining disconnection and short circuit. The mode switching means 14 receives a test signal from an input from a test button or the like, and receives a test signal to switch the detection signal from the fire detection means 10 to the discrimination circuit (first switch S1, The second switch S2) is provided.
The fire detection means 10 applies a power supply voltage V to a temperature sensor 10a and a resistor R4 connected in series, and takes out the voltage across the resistor R4 as a detection signal. Since the temperature sensor 10a is composed of a thermistor exhibiting a negative temperature characteristic, if the ambient temperature rises, the voltage across the resistor R4 increases, while if the ambient temperature falls, the voltage across the resistor R4 becomes Get smaller.

  The fire alarm discriminating means 11 is a discriminating circuit constituted by a comparator C1 that adds a voltage of a reference level EA generated from a power source voltage V by a series circuit of a voltage dividing resistor R1 and a Zener diode ZD1 to an inverting input terminal (−). The detection signal from the fire detection means 10 is input to the input terminal (+). Therefore, when the voltage level of the detection signal exceeds the reference level EA, the fire detection signal is input to the fire alarm processing means 12.

The test discriminating means 13 is composed of a discriminating circuit that performs an internal circuit operation and a discriminating circuit that performs an outline test operation. The discrimination circuit that performs the internal circuit operation is divided from the power supply voltage V by the comparator C2 in which the voltage level EH generated by the voltage dividing resistor R2 and the Zener diode ZD2 is added to the input terminal (+) and the power supply voltage V. A normal operation determination signal is received only when signals are input from both the comparator C3 and the comparators C2 and C3 to which the voltage of the voltage level EL generated by the voltage resistor R3 and the Zener diode ZD3 is applied to the inverting input terminal (−). And a logical product circuit for output. The discriminating circuit that performs the fogging test operation is composed of a comparator C4 that adds the voltage of the reference level EB generated by the series circuit of the voltage dividing resistor R4 and the Zener diode ZD4 from the power supply voltage V to the inverting input terminal (−). A detection signal from the fire detection means 10 is input to the terminal (+). Therefore, when the voltage level of the detection signal exceeds the reference level EB, the fire detection signal is input to the fire alarm processing unit 13. Here, four reference levels and voltage levels are set to EA>EB>EH> EL.
The fire alarm processing means 12 is connected to the fire alarm determining means 11 and the test determining means 13 through separate input ports, respectively, and a fire detection signal and a normal operation determining signal are input to the respective input ports. In response to this, a fire notification and a test notification described later are performed.

In the fire alarm device 1 having such a configuration, first, an operation during normal fire monitoring will be described below.
During fire monitoring, if the ambient temperature of the fire alarm 1 is low, no fire will occur and no action will be taken. If a fire occurs and the ambient temperature rises, a detection signal with a predetermined voltage level will be detected. When the means 10 outputs the fire detection signal to the fire alarm processing means 11 and determines that the voltage level of the detection signal exceeds the reference level EA, the fire alarm determination means 11 sends the fire detection signal to the fire alarm processing means 12. Output. Upon receiving the fire detection signal, the fire alarm processing means 12 activates the counter 12a, counts the fire detection signal sent from the fire alarm processing means 12 every predetermined time, and when the predetermined count value is reached. It is determined that it is a real fire, and a fire alarm signal is output to an alarm unit (not shown).
Specifically, referring to FIG. 3, when the ambient temperature measured by the temperature sensor 10a exceeds approximately 60 ° C., a detection signal exceeding the reference level EA is sent to the fire alarm determination means 11. Here, the reference level EA is set to about 4.5 (V). When the fire alarm determination unit 11 determines that the voltage level of the detection signal exceeds the reference level EA, the fire detection signal is sent to the fire alarm processing unit 12. When the 9-pulse count is counted, the fire alarm processing means 12 determines that it is an actual fire, outputs a fire alarm signal, and from the alarm unit until an alarm stop button (not shown) or the like is operated. Fire is reported. "

Next, the operation during the operation test will be described below.
When a test signal is input to the mode switching means 14 by a test button operation or the like provided in the fire alarm 1, the timer 14b of the relay switching unit 14a is started, and first, until a predetermined time (for example, about 30S) elapses. The first switch S1 is closed by the relay switching unit 14a, and the second switch S1 is opened. Within this predetermined time, an internal circuit test is performed to determine whether the temperature sensor 10a of the fire detection means 10 is outputting within the normal range. More specifically, referring to FIG. 3, when the ambient temperature detected by the temperature sensor 10a is in the range of about 0 ° C. to 40 ° C. during the operation test, the voltage level EL (1.5 (V) ) To voltage level EH (3.5 (V)), a detection signal is output to the test discriminating means 13, and in the test discriminating means 13, the voltage level EL (1.5 (V))) to voltage When it is determined that the voltage level of the detection signal is within the range of level EH (3.5 (V)), a normal operation determination signal is sent to the fire alarm processing means 12 as normal.

That is, if the voltage level of the detection signal output from the fire detection means 10 is within the normal output level range determined by the voltage level EL and the voltage level EH, the normal range is output and there is no disconnection or short circuit. While the normal operation determination signal is output to the fire alarm processing means 12, when the detection signal is lower than the voltage level EL or higher than EH, the normal operation determination signal is output as an abnormality has occurred in the fire detection means 10. I am trying not to. Here, the voltage level EL is set to the voltage level of the detection signal when the ambient temperature of the temperature sensor 10a is approximately 0 degrees, and the voltage level EH is detected when the ambient temperature of the temperature sensor 10a is approximately 40 degrees. The signal voltage level is set.
Upon receiving the normal operation determination signal, the fire alarm processing means 12 sends a test alarm signal to the alarm unit, and the alarm unit reports that it is “normal”, etc. Because it is not made, it can be recognized that there is an abnormality.
Needless to say, when there is an abnormality, it may be configured to notify “abnormal”.

Next, when the predetermined time has elapsed, the first switch S1 is opened by the relay switching unit 14a, the second switch S2 is closed, and the blow test is performed. When the blow test is performed, the fire detection means 10 detects a pseudo fire factor. At this time, the reference level for determining an actual fire is switched to a lower level than when the fire is monitored by switching by the relay switching unit 14a, and the timer 14b counts a predetermined time (for example, about 30S) after the internal circuit operation. To start.
That is, at the time of fire monitoring, if the ambient temperature is detected to be 60 ° C. or higher, a detection signal of the reference level EA or higher is output, and it is determined as an actual fire. The blow test is performed by switching the reference level to a level lower than EA so that it is determined that an actual fire is detected within the range of ℃ and the fire alarm signal is sent from the fire alarm processing means. In other words, since the temperature sensor 10a detects the fire factor at a lower temperature than that at the time of fire monitoring by switching the set voltage level by the mode switching means 14, it can be said that the sensitivity of the temperature sensor 10a is increased.
In FIG. 3, the reference level EA is set to 4.5 (v), and the reference level EB is set to about 4.0 (v). Here, the reference level EB is set within the range of the voltage level EH to the reference level EA, and the closer the voltage value is to the voltage level EH, the faster the exposure test can be performed.

When the dust test is started and the ambient temperature measured by the temperature sensor 10a exceeds approximately 40 ° C., a detection signal of the reference level EB is sent to the fire alarm discriminating means 11, and the voltage level of this detection signal is the reference level EB. If the test discriminating means 13 discriminates that the above has been exceeded, a fire detection signal is sent to the fire alarm processing means 12. When the 9-pulse count is counted, the fire alarm processing means 12 determines that it is an actual fire, outputs a fire alarm signal, and from the alarm unit until an alarm stop button (not shown) or the like is operated. Fire is reported. " Here, the count value counted by the counter 12a of the fire alarm processing means 12 can be set to a value smaller than that at the time of fire monitoring until a predetermined time in the fog test elapses. For example, a place where it was determined that an actual fire was detected by 9-pulse count is switched to 1-pulse count.
According to this, the detection temperature at the reference level is lowered by setting the count value to a small value in addition to the point where a fire is detected when the detection temperature is lower than the actual fire judgment at the time of fire monitoring. In addition, it is possible to perform an operation test more quickly at a low level by reducing the count value.

After a predetermined time has elapsed, the relay switching unit 14a opens the second switch S2 and automatically returns to the fire monitoring state. At this time, since the second switch S2 is opened, the reference level for detecting a fire can be automatically returned to the reference level EA.
Therefore, there is no need for the operator to set the reference level to the original reference level at the time of fire monitoring after the operation test. The fire alarm 1 can be configured.

As described above, the fire detection means having the temperature sensor 10a configured by the thermistor and outputting the detection signal of the voltage level corresponding to the ambient temperature has been described. It can also be applied to smoke detection type fire alarms that detect fires based on the measured smoke concentration. If the configuration is such that a low smoke concentration is determined as an actual fire), an operation test can be performed quickly.
Further, the set reference levels EA, EB, voltage levels EH, EL voltage values, the counted pulse count number, the detection temperature setting by the temperature sensor 10a, etc. are examples, and are not limited thereto. Further, the notification by the alarm unit is not limited to voice notification, but also includes notification by ringing sound, light, and a combination thereof.
In the above description based on FIG. 3, it has been described that the temperature characteristic of the temperature sensor 10a composed of the thermistor changes linearly. However, in reality, there are many hyperbolic changes with respect to the temperature. Reference levels EA and EB and voltage levels EH and EL may be determined according to the curve.

It is a block diagram which shows an example of the principal part structure of the fire alarm of this invention. It is a figure which shows an example of the circuit structure of the block diagram shown in FIG. It is a figure which shows the relationship between the output level (it depends on an ambient temperature rise) of a heat detection signal, and the reference level of a test report and a fire report.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fire alarm 10 Fire detection means 11 Fire alert determination means 12 Fire alert processing means 13 Test discrimination means 14 Mode switching means 14a Relay switching part 14b Timer 15 Alert discrimination circuit

Claims (2)

It is determined whether a fire detection means that detects a fire factor such as smoke or heat and outputs a detection signal, and whether or not the detection signal output from the fire detection means exceeds a set reference level. A fire detection signal is output when it exceeds the limit, and the number of times the above fire detection signal is output is counted every predetermined time. In a fire alarm equipped with an alarm detection circuit that outputs
Having a timer and receiving a test signal, activates the timer and switches and sets the reference level of the alarm determination circuit to a level lower than the original reference level until a predetermined time elapses. , after a predetermined time has elapsed, Rutotomoni comprises a mode switching means for returning to the original reference level,
The alarm determination circuit includes a determination circuit configured to include a determination circuit that performs an internal circuit test for determining whether the fire detection unit is disconnected or short-circuited, and a determination circuit that performs a flash test operation.
At the time of the internal circuit test, at the time of the blow test, a reference level that is lower than the reference level at the time of fire monitoring and different from each other is set, and until the timer has passed the predetermined time, A fire alarm in which the count value is set to a value smaller than that at the time of fire monitoring, and the reference level is set to a reference level for an internal circuit test or a reference level for a blow test . In claim 1,
When the mode switching means receives the test signal, the fire alarm device includes a control contact for switching the detection signal from the fire detection means to the two determination circuits configured in the test determination means .

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