JPH0442719B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a receiver for a fire alarm device, and particularly provides an early warning system that generates very few non-fire alarms.

"Conventional technology" Conventionally, a receiver and multiple analog sensors are connected through a transmission line, and each analog sensor is called periodically from the receiver, and analog quantities such as temperature and smoke concentration are detected from each called analog sensor. Return data indicating the occurrence of the abnormality is sent back to the receiver, and the receiver receives this return data to determine whether it is normal or abnormal, such as a fire outbreak, and when an abnormality occurs, the area where the abnormality occurred and the state of the abnormality are displayed. There is a fire alarm system. For example, JP-A-59-
Publication No. 77594, "Fire Alarm System""Problems to be Solved by the Invention" Such conventional fire alarm devices often generate false alarms. This is because the installation conditions of the location where the analog sensor is installed are slightly different in each case, and this parameter is the cause of false alarms. Accurately knowing the installation conditions for each analog sensor in advance requires time and effort. Therefore, unless the installation conditions are understood, false alarms cannot be reduced even if the receiver uses analog sensors to determine the occurrence of a fire.
Also, since the receiver side judges the occurrence of a fire, it is relatively easy to change the sensitivity, but if the sensitivity is lowered uniformly, it will reduce false alarms overall, but it will not be possible to provide an early warning system. It disappears.

``Means for Solving the Problems'' The receiver of the fire alarm system of the present invention includes a false alarm confirmation switch that is operated when a false alarm is confirmed at the time of a fire alarm, and a false alarm confirmation switch that is operated when the false alarm confirmation switch is operated. ``Action'' consisting of means for changing the fire occurrence judgment criteria of analog sensors to lower sensitivity step by step, or means for changing to sensitivity determined by past returned data. Since the judgment criteria can be easily changed to match the installation conditions, it is possible to provide an alarm system with fewer false alarms.

``Embodiment'' As shown in FIG. 1, the fire alarm system of the present invention includes a receiver RC, a transmission line l extending from the receiver RC to each warning area, and a plurality of devices connected to the transmission line l. It is composed of analog sensors AS1 to ASn. The receiver RC includes a central processing unit MP such as a microprocessor, a storage ME in which programs, data, etc. are stored, an interface IFP for operation and display, and an operation unit such as a numeric keypad and operation switches. CN, display unit DS such as LED and buzzer, interface IFM for transmission,
It is composed of analog sensors AS1 to ASn and a transmission section MD that transmits and receives signals.

The receiver RC is sequentially and periodically analog sensor
Call AS1~n. Each of the called analog sensors AS1 to ASn returns data indicating analog quantities such as temperature and smoke concentration to the receiver RC. The returned data is received by the transmission section MD of the receiver RC and taken into the central processing unit MP via the interface IFM. The central processing unit MP determines whether the returned data is normal or abnormal, and in the event of an abnormality, displays the area where the abnormality has occurred and the state of the abnormality on the display unit DS. Analog sensors also determine the occurrence of a fire.
This is performed based on the magnitude of analog quantities of AS1 to ASn, the amount of change per unit time, or the accumulated value over a predetermined time.

At the time of initial setting, a standard judgment value is set, and the occurrence of a fire is judged based on this value. However, if a person at the scene confirms that it is a false alarm after a fire has been reported, operating the false alarm confirmation switch on the control panel CN determines that the equipment environment in the area where analog sensors AS1 to ASn are installed has exceeded the judgment value for some reason. Then, the judgment standard is changed to low sensitivity, the alarm status is restored, and the monitoring status is returned. Also, the storage section of the receiver RC
ME Random, Access, Memory (RAM)
Therefore, the maximum value of the analog data of each of the analog sensors AS1 to ASn is always stored, and the judgment criteria can be changed based on the buffer contents in which this maximum value is stored.

Thus, the receiver of the fire alarm system of this invention
RC can be easily changed to a criterion suitable for the equipment conditions of each analog sensor AS1 to ASn.

Next, a flowchart of the main operation of the receiver RC will be explained based on FIGS. 2 to 4. As shown in FIG. 2, step S1 indicates when the receiver RC is powered on, and first, in step S2, the buffer etc. are initialized and the sensor address number N is set to O. In step S3, it is determined whether address number N is final. If YES, proceed to step S4; if NO, proceed to step S5. Step S4
sets the sensor address number N to O and proceeds to step S5. Step S5 advances the sensor address number N by one step. Step S6 calls the sensor with the address number N set in step S5 and requests return data. Step S7
receives and imports the returned data. Step S8 determines whether a fire has occurred in the area of sensor N from this returned data. If YES (fire has occurred), proceed to step S9; if NO, proceed to step S9.
Proceed to S10. Step S9 drives display units such as indicator lights and buzzers to display a fire alarm, and performs incidental processing such as controlling district bells and smoke prevention equipment as necessary. In step S10, when there is an input from the false alarm confirmation switch, the criterion (sensitivity) for determining fire occurrence of the corresponding sensor is changed, and the process returns to step S3.

FIG. 3 is a flowchart showing an example of the sensitivity change process in step S10. In step S101, it is determined whether or not a fire alarm is being issued. If NO, this routine ends without doing anything. If YES, proceed to step S102. In step S102, it is determined whether or not there is an input to the false alarm confirmation switch.
If NO, this routine ends. If YES, proceed to step S103. Step S103 changes the criteria for determining whether a fire has occurred for the sensor that is issuing an alarm;
Lower the sensitivity by one level. After the fire alarm has been recovered, this routine ends. There is also a method of specifying a sensor number using the keyboard when operating the false alarm confirmation switch, and changing the sensitivity for the specified sensor.

Figure 4 shows another example of the sensitivity change process in step S10.
In the flowchart showing an example, step S111 compares the contents of the maximum value buffer for each sensor with the currently returned data, and updates the buffer contents only when the returned data is larger. and step
S112 determines whether a fire alarm is being reported. NO.
If so, end this routine. If YES, proceed to step S113. In step S113, it is determined whether or not the false alarm confirmation switch is input.
If NO, this routine ends. If YES, proceed to step S114. Step S114 changes the fire alarm level for the sensor that is issuing an alarm. This fire alarm level Si becomes Si=Maxi+α, where Maxi is the content of the maximum buffer. α is a margin and is determined by a fixed value or a percentage of Maxi. In this way, the criteria for determining fire occurrence for sensors that cause false alarms can be easily changed to match the equipment conditions.

``Effects of the Invention'' As explained above, the present invention, when a false alarm is confirmed, changes the magnitude of the criterion value and the address of the sensor when changing the fire occurrence criterion value of the analog sensor that issued the false alarm. This is extremely useful in the disaster prevention industry because it can be easily changed without knowing each detail, and even after installation, it is possible to easily create an alarm system with fewer false alarms.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration block diagram of the fire alarm system of the present invention, FIG. 2 is a flowchart of the same receiver, and FIGS. 3 and 4 are detailed flowcharts of the main parts of the same. RC...Receiver, l...Transmission line, AS1~ASn...
...analog sensor, ME...memory section, MP...
Central processing unit, IFM, IFP...interface, MD...transmission section, CN...operation section, DS...display section.

Claims (1)

[Scope of Claims] 1 Connected to a plurality of analog sensors via a transmission line, sequentially and periodically calling each analog sensor, and receiving analog quantities such as temperature and smoke concentration returned from each called analog sensor. The system receives return data indicating the above, and compares the received return data with judgment reference values set corresponding to each of the above-mentioned analog sensors to determine whether there is an abnormality in the occurrence of a fire, and in the event of an abnormality, drives the display unit, etc. In the receiver of the fire alarm device, which is configured to issue a fire alarm, there is a false alarm confirmation switch that allows operation input only during a fire alarm, and the above-mentioned judgment corresponding to the above-mentioned analog sensor that is judged to be abnormal based on the input of the false alarm confirmation switch. 1. A receiver for a fire alarm system, comprising means for changing only a reference value to a low sensitivity. 2. A patent characterized in that the means for changing only the judgment reference value corresponding to the analog sensor that has been determined to be abnormal to a lower sensitivity comprises means for changing the sensitivity stepwise to a lower sensitivity each time the false alarm confirmation switch is input. A receiver for a fire alarm device according to claim 1. 3. The means for changing only the judgment reference value corresponding to the analog sensor that has been determined to be abnormal to low sensitivity shall consist of means for changing to low sensitivity based on the maximum value of the return data at the time of false alarm stored in memory. A receiver for a fire alarm device according to claim 1, characterized in that: