JPH03282698A - Fire alarm device - Google Patents

Abstract

PURPOSE:To raise a fire alarm in an early stage and surely by using plural smell detectors, and informing a fire in advance by detecting a smell in an initial stage of a fire. CONSTITUTION:As for a first smell detector 1, a detecting element 11 of an SnO2 sintering type which scarcely responds to a burning smell generated at the time of fire but responds easily to alcohol, etc., used daily is used, and as for a second smell detector 2, a detecting element 21 of an SnO2 thin film type which responds easily to a burning small generated at the time of fire but scarcely responds to alcohol, etc., used daily is used. In such a state, when an output of a second smell detector exceeds a prescribed threshold, a fire signal is generated from an alarm circuit in accordance with whether the output of a first smell detector at that time exists in a prescribed range or not. In such a way, a fire can be informed in an earlier stage and more surely than a fire alarm device using a fire sensor of a heat and smoke type.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention uses multiple odor detectors to detect the first 1υ of a fire.
The first stage relates to a fire alarm system that warns of a fire in advance by detecting an odor.

[Conventional wave]

Conventional fire alarm systems are known to have fire detectors that detect heat and smoke generated by a fire, and they are used either alone or in combination to prevent false alarms to determine if there is a fire. Ta.

[Problems with conventional technology]

However, since such a method detects combustion products generated by a fire or its heat, it is difficult to determine a fire early and issue an alarm.

[Problem to be solved by the invention]

In view of the above point 1-, the present invention aims to provide a fire alarm device that detects a burning odor, which is generally generated earlier than combustion products such as heat and smoke generated by a fire, and determines whether there is a fire. The first type is a substance that is difficult to respond to the burning smell that occurs with fire, but is more likely to respond to alcohol, etc. used on a daily basis.
a second odor detector that easily responds to the burnt odor that occurs with a fire but is less likely to respond to everyday use such as alcohol, and a threshold for detecting a predetermined output of the second odor detector. A value detection circuit, a band detection circuit that detects and outputs that the output of the first odor detector is within a predetermined range when the threshold detection circuit operates, and outputs of the threshold detection circuit and the band detection circuit. The invention is characterized in that it is equipped with an alarm circuit that issues a fire signal.

[For production]

When the output of the second odor detector, which easily responds to the burning odor that occurs with a fire, exceeds a predetermined threshold, the output of the first odor detector at that time
A fire signal is emitted from the alarm circuit depending on whether the output of the odor detector is within a predetermined range, so it can notify a fire earlier and more reliably than a fire alarm system that uses heat or ring type fire detectors. be able to.

〔Example〕

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

In the first session, 1 is the first odor detector, and as shown in Figure 2, the detection element is for alcohols that are difficult to respond to the burning odor that occurs during fires, or for alcohols used in daily life, especially aliphatic alcohols. It is composed of an odor detection element made of a SnO□ sintered semiconductor 12 in which Pd is mixed into stannic oxide so as to easily respond to the system, etc., and is equipped with a pair of electrodes 13 and a heater 14. Electrically, it is provided on one side of the bridge circuit 14 as shown in FIG. 2 is a second odor detector, and its detection element 21, as shown in FIG.
The alumina substrate 22-
1=.

A pair of electrodes 2 are formed by forming a Sn○2 thin film 23 on the
4, a heater 25, and its lead wire 26. Electrically, it is provided on one side of the bridge circuit 27 as shown in FIG. 5G.

3 is a memory device 4 as well as a controller for controlling, calculating, and controlling this fire alarm system.
It is a microprocessor that makes decisions.

The storage device 4 is composed of ROM41 and RAM42, and RO
M41 includes a program storage area 411 in which the system program is stored, and the threshold value of the second odor detector 2 and the output of the first odor detector 1 that determines whether the output is within a range that is determined to be a fire. Threshold function to judge A = f(TIAT
A constant storage area 412 in which Δ1) is stored. Further, the RAM 42 includes the cotton area 421 and the odor detector 1.
and a data storage area 422 for storing output data of No. 2.

And specifically, Gorera microprocessor 3 and Be
+M device 4, a threshold detection circuit that detects a predetermined output of the second odor detector 2, a band detector and an alarm circuit that detects and outputs that the output of the first odor detector is within a predetermined range. is configured.

5.6.7 respectively odor detector 1.2 and indicator 8
It is an interface established between.

The operation of the apparatus configured as described above will be explained using the flowchart shown in FIG.

When the start button of the device is pressed (not shown), the device is initialized and connected to the odor detectors 1 and 2 via the interfaces 5 and 6.
The outputs of are temporarily stored in the work area 421 of the storage device 4 as DATAI and 1) ATΔ2 (Sl
).

The output DATA2 of the odor detector 2 is compared with a constant stored in the constant storage area 412 of the storage device 4 (S2)
. As long as the output of the odor detector 2 does not become DATA2≧, the operations 81 and 2 are repeated at a predetermined period.

On the other hand, when the output DATA2 of the odor detector 2 becomes DATA2≧, it is assumed that there is a high possibility that a fire has occurred. -f (to DAT 81) is read out to the work 9 page area 422, and A-f (to DAT 81 is calculated by 7 times (S4)).

When the calculation result becomes 2 (A≦DAT), a burnt odor is generated and it is determined that a fire has occurred (S 5 ), and the occurrence of a fire is displayed on the display 8 via the interface 7.

In FIG. 7, the output of the odor detector 1 in the above embodiment is plotted on X1lIllll, and the output of the odor detector 2 is plotted on the y-axis. Curves A2 and B are obtained when decorative plywood is heated to 11 degrees on a hot plate in case of a fire.
Toluene and ethyl alcohol, which are generated in daily life, are shown by curves B and H, and curve a
The function A and the threshold value K are shown as curves.

In the above embodiment, as the first odor detector, an S n 02 sintered odor detection element was used as an element that does not easily respond to the burnt odor that occurs during a fire, but easily responds to alcohol and the like that are used on a daily basis. In addition, as a second odor detector, snoz F is used as an element that easily responds to the burning odor that occurs during a fire, but is difficult to respond to alcohol, etc. that is used on a daily basis.
If + film type detection element was used, but if the above conditions are not met, the first detector's detector should be a thin film type and the second detector
The detection element of the detector may be constructed of a sintered type. Moreover, any element may be constructed of a thin film type or a sintered type.

(Effects) Since the fire alarm device of the present invention is configured and operates as described below, there is a fire alarm device that can promptly and reliably issue a fire alarm using a plurality of odor detectors. There are benefits to be gained.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of a device according to an embodiment of the present invention, and FIG.
and FIG. 3 are schematic diagrams of the first and second odor detectors,
4 and 5 are circuit diagrams of the first and second odor detectors, FIG. 6 is a flowchart for explaining the operation, and FIG. 7 is a characteristic curve diagram. DESCRIPTION OF SYMBOLS 1... First odor detector, 2... Second odor detector, 11... Detection element of first odor detector, 14...
Bridge circuit, 21... Detection element of second odor detector, 27... Bridge circuit, 3... Microprocessor, 4... Storage device, 41... ROM, 411...
-Program storage area, 412...Constant storage area, 4
2...RAM, 421...Work area, 422...
・Data storage area, 5-7...Interface, 8.
··display. 1st ward 3rd figure ml milk 2nd figure! AS diagram diagram

Claims (3)

[Claims] (1) A first odor detector that does not easily respond to the burnt odor that occurs in fires, but easily responds to everyday alcohol, etc., and a first odor detector that responds easily to the burnt odor that occurs in fires, but that responds to alcohol that is used in everyday life. a second odor detector that is difficult to respond to, etc., a threshold detection circuit that detects a predetermined output of the second odor detector, and an output of the first odor detector when the threshold detection circuit is activated. What is claimed is: 1. A fire alarm device comprising: a band detection circuit that detects and outputs that the threshold voltage is within a predetermined range; and an alarm circuit that issues a fire signal based on the outputs of the threshold detection circuit and the band detection circuit. (2) The fire alarm system according to claim 1, wherein the first odor detector is constructed of a detector that is particularly responsive to aliphatic alcohols. (3) The fire alarm system according to claim 1, wherein the second odor detector is constructed of a detector that particularly responds easily to aromatic compounds including aromatic alcohols and aldehydes.