JP2845928B2 - 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 type fire detectors and storage type fire receivers are designed to reduce the storage time when the detection amount related to fire phenomena such as heat and smoke detected at predetermined time intervals exceeds a predetermined level. The counting is started, and when the value falls below a predetermined level, the counted accumulation time is released, and when the state in which the detected amount exceeds the predetermined level continues for a certain predetermined accumulation time, it is determined that a fire has occurred. I have to. This has the advantage that, for example, non-fire alerts due to transient smoke, such as smoke detectors and possibly cigarettes, are prevented.

[Problems to be Solved by the Invention] However, if the sensor level has fluctuated for a long time over a predetermined level at which accumulation starts even though there is a fire abnormality, the sensor level falls below the predetermined level. Since the counting of the accumulation time is canceled every time, the fire operation is not reached at all, and the report is delayed or unreported.
Such fire patterns are common in smoldering fires, especially when air-conditioning equipment is operating, the air flow is disturbed, and smoke does not come to the ceiling detector installation location. Thus, it is difficult for the sensor to keep detecting a sensor level above a predetermined level. In the conventional storage-type fire alarm device having such a drawback, the detection of a fire may be delayed and the damage may be increased.

Further, as described in, for example, JP-A-56-159792, it is determined whether the sensor level detected at regular time intervals exceeds a predetermined level, and the number of sensor levels exceeding the predetermined level within a predetermined time is determined. However, a storage-type fire alarm device that determines that a fire has occurred when the value exceeds a predetermined value has been proposed. However, since a simple shift register is used as a sensor level storage unit, it is possible to prevent erroneous detection of noise. There was a problem that it could not be achieved sufficiently and lacked reliability.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and uses a RAM as a sensor level storage means, and sets a sensor level for a first predetermined time (5 minutes) at regular time intervals. When the total time exceeding a predetermined level among the sensor levels exceeds a second predetermined time (1 minute), a fire is discriminated, so that erroneous detection of noise is reliably prevented. To provide a storage-type fire alarm device with improved reliability.

[Means for Solving the Problems] It is an object of the present invention to provide a storage-type fire alarm device that can detect a fire early even when the sensor level rises and falls sharply. A sensor level from a fire phenomenon detection unit for detecting a physical quantity relating to a phenomenon is stored for a first predetermined time at fixed time intervals, and an oldest sensor is stored every time a new sensor level is stored. A storage unit comprising a RAM which constitutes a storage area for storing the latest sensor level by erasing the level; and when the new sensor level exceeds a predetermined level, the storage unit is stored in the storage unit. A total time during which the predetermined level is exceeded among the sensor levels is calculated. If the total time exceeds a second predetermined time shorter than the first predetermined time, a fire is detected. Fire determining means comprising a microprocessor for determining that the first predetermined time is set to 5 minutes, and wherein the first predetermined time is set to 5 minutes and the second predetermined time is set to 1 minute. We provide storage-type fire alarms.

[Operation] When the sensor level is stored in the storage means for a first predetermined time (5 minutes), and when the total time of exceeding the predetermined level among the stored sensor levels exceeds 1 minute Fire detection is performed at the same time. This allows the sensor
Even when the level moves up and down due to the waves, a fire can be detected with high accuracy and early.

Example An example of the present invention will be described below with reference to the drawings.

Figure 1 is a present invention is a block circuit diagram showing an embodiment when applied to a fire alarm system analog, in FIG, RE is the fire receiver, SE ₁ ~SE _N, for example a pair of power supply Fire receiver RE via transmission line L such as a signal line
There are a plurality of analog fire detectors connected to. Although the internal circuit of only the _first fire detector SE1 is shown in detail, other fire detectors have the same internal configuration.

In the fire receiver RE, the MPU 1 is a microprocessor, the ROM 11 is a program storage area, the ROM 12 is a storage area of a terminal address map storing addresses of the respective flame sensors, the ROM 13 is a storage area of various constants, and the RAM 11 is a storage area of various constants. , Sensor-level storage area, RAM12 is a work area, TRX1 is a transmission / reception unit composed of a serial / parallel converter, parallel / serial converter, etc., OP is an operation unit having various switches, etc., DP is , A display unit having a display such as a CRT, IF11, IF12, and IF13 are transmission, display, and operation interfaces, respectively.

Further, in the fire detector SE _1, MPU 2, the microprocessor, the ROM 21, the storage area of the program, the RAM 21, a work area, FS is a fire phenomenon detecting unit, there in this embodiment, for example, the light scattering type Good smoke detector. Although not shown, the fire phenomenon detection section FS includes an amplifier, a sample-and-hold circuit, an analog / digital converter, and the like.

TRX2 is a transmission / reception unit similar to TRX1, and IF21 and IF22 are transmission and detection interfaces, respectively.

The operation of FIG. 1 will be described with reference to a flowchart of FIG. 3 showing a flow chart of a second diagram illustrating the operation of the fire receiver RE, and the operation of each fire detector SE _n.

The fire receiver RE collects sensor level SLV sequentially from 1st fire detector SE ₁ to N-th fire detector SE _N intended to make the fire discriminating operation. No. 1 for one cycle or operation of collecting 1 around fraction from the fire detector SE ₁ to the fire detector SE _N of N numbers is carried out in a substantially constant time interval of five seconds, etc. For example, therefore, each fire detector Detects the physical quantity according to a command from the fire receiver RE at the predetermined time interval and sends out the sensor level SLV.

In operation of the fire receiver RE for fire detector SE _n of n-th, first, the address of the n-th fire detector SE _n is the additional data return command is sent onto the transmission line L (step 203; FIG. 2). N in response to the data return command
Data from the fire detector SE _n , that is, sensor level SLV
Is returned (Y in step 204), the return data SLV is read from the interface IF11 and stored in the sensor level storage area RAM 11 (step 205).

In the sensor level storage area RAM11, sensor levels for a first predetermined time, for example, 5 minutes, are collected and stored for each fire detector, and a new sensor level SLV is read. The oldest data is discarded each time.

Next, the data returned just now, ie sensor level SL
V is compared to a predetermined level A stored in the storage area ROM13 for the various constants, if response data SLV is smaller than the predetermined level A (N in step 206), detected in the n-th fire detector SE _n The determined sensor level SLV is determined to be normal, and the process proceeds to step 210 through a fire determination or monitoring operation for the next fire detector.

If the transmission data SLV is equal to or higher than the predetermined level A (Y in step 206), the sensor level storage area RAM11
The number COUNT of data exceeding the predetermined level A among the sensor levels stored in is counted (step 207),
The number COUNT of the data is compared with a second predetermined value B (step 208).

In the present embodiment, it is determined that a fire has occurred when the total time during which the sensor level SLV was equal to or higher than the predetermined level A is a second predetermined time, for example, 1 minute. Therefore, the second predetermined value B is set to a value obtained by dividing the second predetermined time by a certain time interval at which the collecting operation of each sensor described above is performed.

As a result of the comparison, if the number COUNT of data is smaller than the second predetermined value B (N in step 208), step 210
The process proceeds to the fire detection or monitoring operation of the next sensor via.

If the data count COUNT is equal to or greater than the second predetermined value B (Y in step 208), a fire operation such as displaying the address of the sensor on the display unit DP via the interface IF12 is performed (step 208). 209), which allows the fire receiver R
The operator at E can know that a fire has occurred at the place where the fire detector is installed.

FIG. 3 is a flowchart for explaining the operation performed in each fire detector. When any transmission signal is received via the transfer line L (Y in step 301), the address associated with the transmission signal is received. Is determined whether it matches the self address stored in the storage area ROM 21 (step 302), and if it matches the self address, it is determined whether it is a data return command (step 30).
3).

Now, the received transmission signal is transmitted to the n-th fire detector SE transmitted from the receiver RE to the transmission line L in step 203 of FIG.
_{If the} command is a data return command for _n (Y in step 303), the sensor level SLV detected by the fire event detection unit FS is read from the interface IF22 (step 30).
4) By setting it in the interface IF21, it is returned from the transmission / reception unit TRX2 (step 305). As a result, a return signal is received in step 204 of FIG.

As described above, since the fire receiver RE performs data collection from all fire detectors at regular time intervals,
Each fire detector receives a data return command from the fire receiver RE at regular time intervals.

If the received transmission signal is not a data return command (N in step 303), since it is a type code command, a code representing the type of the fire sensor stored in the storage area ROM21 is set in the interface IF21. Thus, the signal is transmitted from the transmission / reception unit TRX2 onto the transmission line L (step 306), but this operation is not directly related to the present invention.

Note that the first and second predetermined times are, as described above,
It is appropriate to set the time to about 5 minutes and 1 minute, respectively, so that the fire can be determined with high reliability without hindering early detection of the fire.

Further, since the sensor level is directly stored in the RAM 11, when the new sensor level exceeds the predetermined level A, the past sensor levels may be sequentially compared in a similar manner, and processing is easy.

In addition, since a predetermined level for each type may be read from the ROM 13 serving as a storage area by the fire determining means including a microprocessor, even if the type of the fire detector SE is different, the accumulation type fire is reliably performed by the same procedure. Not only can it distinguish between smoke and heat, but also the level of sensitivity, etc.
By setting in the ROM 13, various constants can be easily switched.

In the above-described embodiment, the case where the present invention is applied to an analog fire alarm device that performs a fire determination using a fire receiver or a repeater based on a sensor level transmitted from an analog fire sensor has been described. However, the present invention can also be applied to a fire alarm device in which a fire detector itself determines a fire and sends a fire signal and / or an address signal to a fire receiver or a relay. In such a case, the program stored in the storage area ROM 11 and various constants in the storage area ROM 13 are stored on each fire detector side, and the sensor-level storage area RA is stored.
M11 may be provided for each fire detector.

[Effects of the Invention] As described above, according to the present invention, the sensor level is stored in the storage means for the first predetermined time of 5 minutes, and the stored sensor level exceeds the predetermined level. When the total time reaches a second predetermined time of one minute, it is determined that a fire has occurred. Therefore, even if the sensor level fluctuates with a wave, the fire can be detected with high accuracy and early. There is an effect that can be found.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block circuit diagram showing a storage type fire alarm device according to an embodiment of the present invention, and FIG. 2 is a fire receiver of FIG.
FIG. 3 is a flowchart for explaining the operation of the RE,
2 is a flowchart for explaining the operation of each fire detector of FIG. In the figure, RE is a fire receiver, ROM 13 is a storage area for various constants, RAM 11 is a storage area for a sensor level, DP is a display unit, OP is an operation unit, SE _{1 to} SE _n are fire detectors,
FS is a fire phenomenon detection unit.

Claims (1)

(57) [Claims] 1. A sensor level from a fire event detection unit for detecting a physical quantity relating to a fire event is stored for a first predetermined time at predetermined time intervals, and one new sensor level is stored. Storage means comprising a RAM constituting a storage area for storing the most recent sensor level, and when the new sensor level exceeds a predetermined level, Calculating a total time exceeding the predetermined level among the sensor levels stored in the storage means, and when the total time exceeds a second predetermined time shorter than the first predetermined time, A fire determining means comprising a microprocessor for determining that a fire has occurred, wherein the first predetermined time is set to 5 minutes and the second predetermined time is set to 1 minute. Storage type fire alarm system according to claim.