JP2711105B2 - Storage type fire alarm - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to an accumulation type fire alarm device for judging a fire abnormality based on a detected amount of heat, smoke, light, gas or the like.

[Prior Art] Conventionally, storage fire detectors and storage receivers are known as storage fire alarms. In these storage type fire detectors and storage type receivers, the detection amount of fire phenomena such as heat, smoke, light or gas exceeds a predetermined level, for example, a fire determination level, and the state is kept for a predetermined time, that is, over a storage time. If the fire is continued, it is judged that a fire has occurred. In the case of a storage type fire detector, a fire signal is transmitted to the receiver, and in the case of a storage type fire detector, a fire occurrence is notified.

There are two more types of storage type receivers.
For example, as disclosed in Japanese Patent Publication No. 45-35862, a detector is connected to a detector that outputs a normal fire signal, and when a fire signal is received from the detector, the detector is set to a predetermined value. Time recovery, after recovery, if the sensor is operated again within the second predetermined time, it is determined that a fire, and as a second type, an analog sensor is connected to the receiver, For example, if the digitized analog amount signal output from the sensor exceeds the fire determination level, the timer is operated, for example, if the analog amount signal continues to exceed the fire determination level while the timer is operating. Some are known to be fires.

In any of the conventional storage-type fire alarm devices described above, in any case, a fire is determined only when the detected amount of the physical quantity continuously exceeds a predetermined level for a predetermined time. For example, in the case of a photoelectric smoke sensor that detects smoke, non-fire alarm is prevented by transient smoke such as cigarettes.

However, this order if it is it is a condition that has continued to detect the amount of more than a predetermined level, for example, as shown in FIG. 4, the detection amount or sensor output level SLV once exceeds a predetermined level A at time t ₁ , then, even if in reduced for reasons such as a fire phenomenon has been extinguished, if it is still higher than a predetermined level, at time t ₂ after a predetermined time, a fire alarm signal as shown in the lower part of FIG. 4 There is a problem that an alarm is issued. Further, even when smoke temporarily enters the environment and the sensor output level rapidly rises and then gradually decreases, a fire abnormal signal is similarly issued and a non-fire report results.

[Problems to be Solved by the Invention] As described above, in the conventional storage-type fire alarm device, the operation is performed only for the time exceeding the predetermined level. There is a problem that malfunction occurs when the detection level is maintained at a predetermined level or more for a predetermined period of time despite the fact that the detection amount is reduced in the middle like sex smoke.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned conventional problems, and the sensor output level has a tendency to be inclined at a predetermined value or more;
For example, by making the timer count up only when there is a rising trend, and by outputting a fire abnormality signal when the timer time reaches a predetermined accumulation time, a more reliable accumulation type fire alarm device can be provided. It is intended to be realized.

Therefore, according to the present invention, a fire phenomenon detection section (FS) that detects a physical quantity related to a fire phenomenon and outputs a sensor output level corresponding to the physical quantity, and the sensor output level (SLV) from the fire phenomenon detection section. A fire alarm device including a fire discriminating means (step 311) for performing a fire discrimination based on the sensor output level when the value of the sensor output level from the fire phenomenon detection unit is equal to or higher than a predetermined level (A). slope determining means for determining the slope (S _T) at the current time (step
307 and 308) and accumulate time (T) when the inclination determined by the inclination determining means indicates a tendency equal to or greater than a predetermined value, and store time (T) when the inclination is less than the predetermined value.
And a first timer means (RAM2, steps 309 and 310) for temporarily stopping the accumulation of..., Whereby the fire discriminating means makes the time (T) accumulated by the first timer means a predetermined time (T). A storage-type fire alarm device characterized in that it is determined that a fire has occurred when the storage time (T ₀ ) has been reached.

According to another aspect of the storage type fire alarm device of the present invention, in addition to the inclination determining means and the first timer means of the storage type fire alarm device, a sensor output level from the fire phenomenon detection unit is provided. The second timer means (RAM2, RAM2) for counting the elapsed time (LT) when the value of
Step 305), whereby when the elapsed time (LT) counted by the second timer means reaches a predetermined time limit (LT ₀ ) longer than the predetermined accumulation time, the fire determination means To make a fire.

[Operation] The slope determining means determines the current slope of the sensor output level when the value of the sensor output level from the fire phenomenon detection section is equal to or higher than a predetermined level, and the first timer means determines the slope. Only the time during which the slope determined by the means indicates a tendency that is equal to or greater than a predetermined value, for example, a rising tendency, is accumulated, whereby the time accumulated by the first timer means reaches a predetermined accumulation time. Therefore, even if the predetermined level is continuously exceeded for a certain period of time, the accumulation timer does not advance while the sensor output level is decreasing, and the operation is suspended.
The function of preventing malfunction from transient smoke is further ensured.

In the case where the apparatus further includes second timer means for counting the elapsed time when the value of the sensor output level from the fire phenomenon detection unit is equal to or higher than a predetermined level, the elapsed time counted by the second timer means Is determined to be a fire when a predetermined time limit is reached, thereby reducing the possibility of unreporting.

[Embodiment] Hereinafter, an embodiment of the present invention will be described using a photoelectric smoke sensor as an example, but prior to that, the operation of the present invention will be described.

FIGS. 1A and 1B are graphs showing two examples of a rising state of smoke for explaining the operation of the present invention. In both figures, the vertical axis indicates the sensor output level SLV in the upper part.
The middle row shows the ON / OFF state of the accumulation timer, the lower row shows the time count value of the accumulation timer, that is, the accumulation time T, and the time count value of the time limit timer, that is, the elapsed time LT, respectively, and the horizontal axis shows Time t is shown.

FIG. 1A shows a case in which a fire operation is not performed, that is, a fire abnormality signal is not issued, and the sensor output level SL
V exceeds the predetermined level A at the point a, at which point the accumulation timer is started and turned on as shown in the middle part of the figure. Between a and b, the sensor output level SLV rises, and the rate of increase, that is, the slope, is a predetermined slope K (K is appropriately selected according to environmental conditions, and is, for example, 0 or a value around 0 in consideration of noise or the like. Is chosen)
As shown in the lower part of FIG. 1A, the accumulation time T of the accumulation timer increases. However, since the sensor output level SLV continues to decrease between b and c, that is, the slope is smaller than the predetermined slope K, the accumulation time T of the accumulation timer is not increased as shown in the lower part, and the value is maintained as it is, When the sensor output level SLV falls below the predetermined level A at the point c, the accumulation timer is cleared. As a result, the sensor is not operated, so that a malfunction due to a transient environmental change such as tobacco is prevented.

FIG. 1B shows a case where a fire operation is performed, that is, a case where a fire abnormality signal is issued, and a sensor output level SL is generated.
When V exceeds the predetermined level A at the point d, the accumulation timer is started and turned on as shown in the middle part of FIG.
Since the sensor output level SLV rises between 1 and e,
As shown in the lower part of the figure, the accumulation time T of the accumulation timer increases. Since the sensor output level SLV is decreasing between the points e and f, the accumulation time T of the accumulation timer is kept unchanged without increasing, and similarly, after the sensor output level SLV exceeds the predetermined level A, When the output level SLV is rising, that is, in the sections de, fg, hi, j
Between −k, the accumulation timer is activated and the accumulation time T continues to increase. Then, the total operating time of the accumulation timer, i.e. accumulation time T is to reach a fire operation in a predetermined storage time T ₀ at k points are performed.

As described above, the accumulation timer counts up only when the sensor output level SLV is rising, so that the fire operation is performed when the sensor output level SLV is increasing or decreasing while the sensor output level SLV is generally increasing. As a result, a highly reliable storage type alarm device can be realized.

1A and 1B, the time count value by the time limit timer, that is, the elapsed time LT is also shown in addition to the accumulation time T by the accumulation timer.
LT represents the total elapsed time since the sensor output level SLV exceeded the predetermined level A. This time limit timer is provided for the following reason. That is, the sensor output level SL
V becomes the accumulation timer is turned on exceeds a predetermined level A, then, when the sensor output level SLV is repeatedly increases and decreases at least predetermined level A, it is considered that the accumulation time T is not quite reached the predetermined accumulation time T ₀ . In such a case, in the present invention, the elapsed time LT after the sensor output level SLV exceeds the predetermined level A is set to a predetermined limit time LT ₀ (L
If T> LT ₀ ) is reached, the possibility of a fire is considered to be high, and the fire operation is actively performed.

Note that the predetermined level A, the predetermined accumulation time T ₀ , the time limit LT
_{0 and the} predetermined inclination K can be appropriately determined depending on the use of the room in which the sensor DE is installed, the height, the volume, the time, the presence or absence of noise, and the like.

FIG. 2 shows an embodiment in which the present invention is applied to a smoke type fire detector. In FIG. 2, RE is a receiver, L is a plurality, for example, a pair of a power / signal line, a dashed line. The circuit part DE shown therein is a plurality of fire detectors connected to the receiver RE by a power / signal line L, and here only one fire detector is shown.

In the fire detector DE, FS is a fire detector, and in this embodiment, a scattered light type smoke detector is shown.

MPU is a microcomputer, OSC is an oscillating unit that oscillates a clock, ROM1 is a storage area of the program shown in the flowchart in FIG. 3, ROM2 is a storage area of a predetermined level A, and ROM3 is a predetermined area as a fire determination reference. storage area of the storage time T ₀ and time limit LT ₀ of the ROM 4, a storage area of a predetermined slope K of the sensor output level, RAM 1, the storage area of the sensor output level SLV is loaded from the fire phenomenon detecting portion FS, RAM 2 Is a time counter storage area as a timer for counting the accumulation time T and the elapsed time LT, RAM3 is a work area, and TAX is a transmission / reception unit connected to the receiver RE. In addition, the smoke sensor, ie, the smoke detection room of the smoke detection unit FS, has a light emitting diode LED that is lit in a predetermined cycle by the oscillation circuit 12 and the light emitting circuit 14, and is proportional to the concentration of the smoke when the smoke flows into the smoke detection room. And a solar cell SB that receives the scattered light. The output from the solar cell SB is amplified by an amplifier 18 through a light receiving circuit 16 and then analog / digital (A /
D) The signal is converted into a digital signal by the conversion circuit 20 and sent to the microcomputer MPU via the interface I / F.

In the case of the embodiment shown in FIG. 2, the fire detector DE is connected to the receiver RE, and the fire detector DE sends only the resulting fire abnormality signal to the receiver RE, and the fire is transmitted from the receiver RE. Detector DE
Polling is not performed on the
X functions only as a fire signal transmitter.

The operation of FIG. 2 will be described with reference to the flowchart of FIG.

After the initial setting (step 301), the sensor output level SLV is read into the work area RAM3 from the smoke detector FS via the interface I / F at a sampling period based on the clock oscillated by the oscillator OSC (step 302). It is compared with a predetermined level A stored in the storage area ROM2 (step 303). As a result of the comparison, if the sensor output level SLV is smaller than the predetermined level A (N in step 303), the sensor output level stored in the sensor output level storage area RAM1 is cleared, and T = 0 and LT = 0 are set. (Step 304), at the next sampling time, Step 3
At 02, the next sensor output level SLV is read.

As a result of the comparison, if it is determined that the sensor output level SLV is equal to or higher than the predetermined level A (Y in step 303), the time limit timer in the time counter storage area RAM2 is used.
LT is incremented by one (step 305). First, the time limit timer LT is set to a predetermined time limit LT ₀ stored in the ROM3.
Is determined (step 306). If the value of the time limit timer LT is equal to or greater than the predetermined time limit LT ₀ (Y in step 306), it is determined unconditionally that a fire has occurred, and a fire signal is output from the fire signal transmission unit TRX, a so-called fire operation. Performed (step 312).

If the time limit timer LT predetermined time limit LT ₀ is smaller than (N in step 360), to calculate the slope of the sensor output level, storing the sensor output level SLV region RAM
Stored in 1 (step 307).

Here, as a method of calculating the gradient of the sensor output level, for example, a plurality of sensor output levels are stored in the storage area RAM1.
Various types of storing the SLV and calculating the gradient of the sensor output level at the present time based on the value of the sensor output level SLV can be considered, and any of them can be adopted in carrying out the present invention. However, here, as the simplest example, two sensor output levels, the sensor output level read at the previous sampling time and the sensor output level read at the current sampling time, are stored in the storage area RAM1.
The following describes an example in which the inclination is obtained from the difference between the sensor output levels.

Therefore, in step 307, of the two sensor output levels already stored in the storage area RAM1, the older one, that is, the one stored as the previous sensor output level is discarded and stored as the current sensor output level. This is stored as the previous sensor output level, and the sensor output level SLV just read from the smoke detector FS this time is stored in the storage area RAM1 as the current sensor output level.

Then, data stored in the storage area RAM 1, i.e. the slope of the moment of the sensor output level calculated by taking the difference between two sensor output level is stored in the work area RAM3 it as S _T (Step 308).

Current sensor output level gradient in work area RAM3
When S _T is stored, the inclined-out S _T is stored in the storage area ROM 4, is compared with a predetermined slope K predetermined, S _T
Is smaller than K (N in step 309), step 302
Then, the next sensor output level is read at the next sampling time.

If the slope S _T at the moment of the sensor output level is higher K (Y in step 309), the value of the accumulation timer T which has been accumulated so far in the counter storage area RAM2 time is incremented by one (step 310), the value of the accumulation timer T that is bulking min, then compared with the predetermined accumulation time stored in the storage area ROM 3 T ₀ (step 31
1).

Result of the comparison, if the value of the accumulation timer T is equal to or greater than the value of the predetermined accumulation time T ₀ is determined that a fire abnormality (Y in step 311), the fire operation for outputting a fire signal from the fire signal transmitting section TRX Will be performed (step 312).

Result of the comparison, if the value of the accumulation timer T is determined to be smaller than the value of the predetermined accumulation time T ₀ (N in step 311), reads the new sensor output level at step 302 every sampling timing, a step 303 The operation from is performed in the same manner. That is, steps 305 and 30 are performed according to the sensor output level read at each sampling time.
8 and 310 are calculated, and the sensor output level SLV
While the value of the time limit timer LT is determined to be equal to or greater than the predetermined level A in step 303,
If LT ₀ or more (Y in step 306), or if the value of the accumulation timer T is equal to or more than the value of the predetermined accumulation time T ₀ (Y in step 311), a fire operation is performed. before at 306 or 311 is determined to become T ≧ T ₀ or LT ≧ LT _0, if the sensor output level SLV is below a predetermined level a (N in step 303), T, LT, and the contents of RAM1 clear After that (step 304), the state returns to the normal monitoring state.

In the above-described embodiment, the case where the present invention is applied to the fire alarm device in which the fire detector DE performs the fire discrimination and transmits the fire signal and / or the address signal to the receiver has been described. The device is an analog fire detector that transmits a physical quantity signal of the detected fire phenomenon, and a so-called analog type that performs a fire discrimination based on the physical quantity signal transmitted from the analog fire detector by a receiver or a relay device. It is also possible to apply the present invention to the above-mentioned fire alarm device.

As described above, in the case where the present invention is applied to an analog fire alarm device in which a receiver or a relay receives a digital phenomenon of a fire phenomenon from an analog sensor and determines a fire by receiving an analog amount signal converted into a digital signal, for example. 2, a microcomputer MPU is provided in the receiver RE, and ROM1 to ROM4, RAM1, RAM2, and the like are transferred from the sensor DE to the receiver RE. In the receiver RE, RAM1 and RAM2 are provided by the number of connected analog sensors. And receiver
A program for polling a plurality of analog sensors and sequentially reading analog quantity signals is added to the ROM 1 relocated to the RE, and each time an analog quantity signal is read, a fire determination is performed according to the flowchart of FIG.

On the other hand, the sensor DE determines whether or not polling has been received from the receiver RE, and when polling has been received, reads the sensor output level SLV from the fire phenomenon detection section FS and reads the transmission / reception section T.
A ROM storing a program to be transmitted from the RX to the receiver RE is provided.

[Effects of the Invention] As described above, according to the present invention, a fire phenomenon detection unit that detects a physical quantity of a fire phenomenon and outputs a sensor output level corresponding to the physical quantity is used, and the sensor output level is inclined to a predetermined value or more. Only when there is a certain time, the timer is counted up, and when the timer time reaches a predetermined accumulation time, a fire abnormality signal is output, so that a more reliable accumulation type fire alarm device without false alarm can be realized. This has the effect.

[Brief description of the drawings]

1A and 1B are graphs for explaining the operation of the present invention, FIG. 2 is a block circuit diagram showing a fire alarm device according to an embodiment of the present invention, and FIG. FIG. 4 is a flowchart for explaining the operation, and FIG. 4 is a graph for explaining the prior art. In the figure, RE is a receiver, DE is a sensor, FS is a fire detector, MPU is a microcomputer, ROM1 is a program storage area, ROM2 is a predetermined level storage area, ROM3 is an accumulation time storage area, and ROM4 is a predetermined slope. storage area, the sensor output level storage area RAM 1, RAM 2 the time counter storage area, RAM 3 is a work area, a is the predetermined level, T ₀ is the storage time, K is a predetermined slope, LT ₀ is the time limit.

Claims (2)

(57) [Claims] 1. A fire phenomenon detecting section for detecting a physical quantity of a fire phenomenon and outputting a sensor output level corresponding to the physical quantity,
A fire alarm device comprising: a fire discriminating unit that performs a fire discrimination based on the sensor output level from the fire event detection unit.When the value of the sensor output level from the fire event detection unit is equal to or higher than a predetermined level, Slope determining means for determining the current slope of the sensor output level; and when the slope determined by the slope determining means indicates a tendency equal to or greater than a predetermined value, time accumulation is performed, and the slope is determined by the predetermined value. And first timer means for temporarily stopping the accumulation of the time when the time is less than the predetermined time, whereby the fire determination means has determined that the time accumulated by the first timer means has reached a predetermined accumulation time. A storage-type fire alarm device characterized in that a fire is sometimes determined. 2. The apparatus according to claim 2, further comprising second timer means for counting an elapsed time when the value of the sensor output level from said fire phenomenon detecting section is equal to or more than a predetermined level, whereby said fire discriminating means is capable of detecting said second fire. 2. The storage type fire alarm device according to claim 1, wherein when the elapsed time counted by the timer means reaches a predetermined time limit longer than the predetermined storage time, it is determined that a fire has occurred.