JP2511273B2 - Fire detector - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fire detection device suitable for a building provided with air conditioning equipment.

When there is a person in the building, as a technique for preventing the false alarm of the fire alarm device due to non-fire smoke generated during smoking or cooking, there is known in Japanese Utility Model Publication No. 59-63787 and Japanese Patent Publication No. 57-141791. Has been.

The fire alarm device disclosed in No. 59-63787 is
By changing the sensitivity of the smoke detector by the manned / unmanned switching signal from the manned / unmanned switching unit, it is possible to detect quickly with some smoke and heat when manned, but quickly with unmanned. In this way, false alarms due to non-fire smoke can be prevented.

The malfunction prevention device of the fire detection device disclosed in Japanese Patent Laid-Open No. 57-141791 detects the presence or absence of a person in the detection area by the output of the person detector, or the presence or absence of a person in the elevator during the car stop time. In order to prevent malfunction of the fire detection device due to non-fire smoke, the sensitivity of the fire detection device is changed depending on the presence or absence of people by detecting the presence of people in the building with a clock and calendar. It is a thing.

However, the above-mentioned known technology is a technology for preventing false alarms that tend to occur when a person is present as a situation at the detection location,
This is different from the technique of the present invention, which mainly prevents false alarms and late alarms caused by the operating condition of the air conditioner.

In other words, in the above-mentioned known technology, there is no possibility that the presence or absence of people, which is the situation at the detection location, changes the smoke density that acts on the fire detector when a fire occurs.

However, in a building equipped with air-conditioning equipment, the air-conditioning equipment is always in operation while people are in the building, and depending on the operating conditions of the air-conditioning equipment, the smoke concentration that acts on the fire detector during a fire may be dependent. It is expected that the fire detection device will change, and the present invention proposes a fire detection device devised so that a fire notification can be promptly and reliably carried out regardless of the change in smoke concentration due to the operating condition of the air conditioning equipment. It is a thing.

(Prior Art) The operating condition of an air conditioner is appropriately controlled depending on the number of people in the room, the state of the outside air, and the like, and, for example, the number of ventilations per hour is appropriately adjusted.

In such a case, when a fire occurs, smoke has a large degree of diffusion and dilution depending on the operating conditions of this air conditioning equipment, and it is expected that the detected smoke concentration will fluctuate considerably. Depending on the operating status of the equipment, it is expected that false information, false alarms, or late information will occur.

In addition, false alarms, missed alarms, or late alarms may depend on the location of the fire detector and the conditions of the room in which it is installed.

That is, in recent years, many buildings such as high-rise buildings or so-called intelligent buildings adopt a large room with a small floor area and a large floor area.

In such a building, as shown in the plan view of FIG. 3 and the modeled front view of FIG. 4, respectively, the ceiling 3 formed by the ceiling 1 and the slab 2 is connected to the plenum chamber ( The partition 4 which is configured as an inflatable chamber and supports the slab 2 such as beams.
Are divided into compartments R ₁ , R _2, etc.

The ceiling 1 has a slit-like intake port 5 and air outlet 6
Are provided in an appropriate number, the air in the room 7 is sucked into the ceiling 3 from the intake port 5, the air volume is controlled by the control valve 8, and the exhaust pipe 9
The air, which is discharged from the outside to the outside and is conditioned by an air conditioning facility (not shown), is supplied to the room 7 from the air supply pipe 11 through the air outlet 6 after controlling the air volume by the control valve 10.

In such a plenum chamber method, the ceiling 3
Since it constitutes a part of the exhaust duct, in order to reliably and quickly detect the smoke of a fire that has occurred, in addition to the ceiling surface which is the detection position in a normal room without a plenum chamber, the ceiling 3 It is also possible to install a fire detector inside.

Furthermore, in the case of such a plenum chamber, it is expected that the diffusion and dilution of smoke depending on the operating condition of the air conditioning equipment will be considerably different from that in a normal room.

(Problems to be Solved by the Invention) As described above, the smoke of a fire that is generated largely changes in its diffusion and dilution depending on the operating condition of the air conditioning equipment, and further, air conditioning is performed. Since it is considered that the diffusion of smoke changes depending on the structure of the room, that is, whether or not the plenum chamber method is used, a fire detection system suitable for such various situations must be investigated.

(Means for Solving Problems) The present invention has been researched and devised so that fire detection is always reliable and quick in response to changes in smoke diffusion and dilution depending on operating conditions of air conditioning equipment. The structure is, therefore, a fire discrimination means having a plurality of fire discrimination criteria for discriminating a fire based on the output of the fire phenomenon detection means, a reporting means for reporting a fire occurrence based on the output of the fire discrimination means, and an operation of the air conditioning equipment. A fire detection device having a receiving means for receiving information and a switching means for switching a fire discrimination reference of the fire discriminating means according to an output of the receiving means.

(Operation) As the operation information of the air conditioning equipment, for example, the operation stop or the number of ventilations per hour during operation is received by the receiving means, and the output of the receiving means based on this is used to determine the fire determination criteria of the fire determining means. Are switched.

When a fire phenomenon occurs, the smoke is detected by the fire phenomenon detection means and compared with the fire discrimination standard by the fire discrimination means, and the fire discrimination means judges whether or not to notify as a fire.

As described above, since the fire discrimination standard of the fire discrimination means is switched based on the operation information of the air conditioning equipment, even when the smoke is sufficiently diluted while the air conditioning equipment is in the full operation state, for example. The fire judgment means is used to switch to an appropriate fire judgment standard, and fire notification can be performed reliably and promptly regardless of the operating condition of the air conditioning equipment, without causing false alarms, late alarms, or false alarms. Is.

(Example) Next, an example of the present invention will be described.

Examine how the smoke density of the fire is diffused or diluted depending on the operating condition of the air conditioning equipment, and determine the appropriate fire discrimination criteria to prevent missed fire alarms according to the operating conditions. In order to find out according to the installation location of each vessel,
We conducted the following experiment.

(1) Conditions of the experiment The building used for the experiment uses the room shown in Fig. 4 as an example of the plenum chamber method, and the fire is detected in the room 7 with a room area of 150 m ² (in the solid line in Fig. 3). When the fire detector S is provided on the ceiling 1 near the center (shown) (the conventional installation position where the fire detector is provided in the room 7), the communication port 12 formed on the partition 4 inside the ceiling 3 The fire detector P was installed near each of the above.

For each of the fire detectors S and P, a smoke-sensing type is used, in which the smoke concentration is represented by the light receiving amount of the light receiving unit corresponding to the light emitting unit in terms of extinction rate% / m per 1 m. Install a type 1 sensor equivalent that operates at 5% / m and a type 2 sensor equivalent that operates at 10% / m, until these fire detectors are activated. The newspaper was burned as a burnt piece at the fire point F, and the weight of the burned burnt piece at that time was measured.

In either case, when the smoke generated at the fire point F reaches the ceiling 1, it flows along the ceiling ₁ and enters the compartments R ₂ and R ₁ from the intake port 5 and reaches the fire point F. There are two flows, one that enters the compartment R ₁ from the nearby compartment R ₂ through the communication port 12 of the partition 4.

And while the air conditioning equipment AC is operating,
The flow of smoke along the ceiling 1 is diffused and diluted by the air blown from the air outlet 6, and the compartment R ₂
In the ceiling space 3 of R ₁ and R ₁ , smoke sufficiently flows in from the suction port 5, so that the concentration of smoke is increased in the ceiling space 3 on the contrary.

(2) Experimental results Fig. 5 shows the experimental results.

(A) When the fire detector S is provided on the ceiling 1 (○.
●) When the air conditioning equipment is stopped, even if the combustion amount of the burned pieces is about 80g, the fire detector S with a sensitivity of 5% / m or 10% / m
While the air conditioner is operating, the smoke density in the ceiling 1 tends to decrease when the air conditioning equipment is operating, and when operating at a ventilation rate of 5 times / h, when the sensor is 5% / m. , About 100g, 10%
A sensor of / m requires about 160g of burnt pieces for each operation.

Thus, as the number of ventilation increases, the smoke along the ceiling 1 is diluted and diffused by a large amount of air blown out from the air outlet 6, and is sucked from the intake port 5 to reduce the concentration. Therefore, it is necessary to switch the fire determination standard from the low sensitivity side to the high sensitivity side as the ventilation frequency increases.

(B) When the fire detector P is provided on the ceiling 3 (△.
▲) When the air conditioning equipment is stopped, the fire detector P with a sensitivity of 5% / m
It operates by burning about 100 g of burnt pieces, and about 10 g / m of burned pieces requires a large amount of about 180 g of burnt pieces, whereas when the air-conditioning equipment is operated, the ceiling 3 Smoke density tends to be increased, and when operating at a ventilation rate of 5 times / h, about 70g with a 5% / m sensor and about 90g with a 10% / m sensor The fire detector P operates by each piece.

When the air conditioning equipment is stopped, the smoke in the room 7 only enters the ceiling space 3 from the intake port 5 only by natural convection, and the smoke density in the ceiling space 3 becomes low, but the air conditioning equipment is operated. Then, as the number of ventilation increases, smoke is forcibly sucked from the intake port 5 to the ceiling 3 and the air blown out from the air outlet port 6 pushes out the smoke in the room 7 to the intake port 5.
The smoke density in the ceiling 3 is higher than that when the air conditioning is stopped.

Due to these facts, it is necessary to switch the fire discrimination standard from the high-sensitivity side to the low-sensitivity side, contrary to the case of the ceiling surface installation, as the ventilation frequency increases.

(3) A preferred embodiment of the fire detection device.

Based on the above experimental results, an example of a fire detection device devised so that a fire notification can be promptly made without error by appropriately switching the fire discrimination standard according to the operating condition of the air conditioning equipment, is shown in FIG. 2 and FIG. 2, respectively.

The fire detection device shown as an example in FIG.
Alternatively, the fire discriminating means in the fire receiver RE is composed of a plurality of fire sensors SE which are provided in the ceiling 3 and output signals according to the analog amount of the detected fire phenomenon, and a fire receiver RE.
The 36 fire determination standards are configured to be switched based on the operation information of the air conditioning equipment AC that performs air conditioning of the place where the fire sensor SE is provided.

That is, the fire sensor SE as a fire phenomenon detecting means is a fire phenomenon detecting means 21 including a photoelectric smoke detector.
And an A / D converter 26 for converting the analog output value of the fire phenomenon detection means 21 into a digital value, and a signal processing unit 27 composed of an MPU or the like for signal processing the output of the A / D converter 26,
It has a transmitting / receiving unit DA including a transmitting / receiving circuit 28.

The fire receiver RE that receives the output of the transmission / reception unit DA and performs fire determination and fire notification is a transmission / reception unit 34 that transmits and receives a signal to and from the fire sensor SE, and a reception circuit that receives operation information from the air conditioning equipment AC. 35, the switching means 25 for switching the fire discrimination standard of the fire discrimination means 36 by the output of the receiving circuit 35, the MPU, etc., the fire discrimination means 36 for discriminating the fire, and the output of the fire discrimination means 36 to identify the fire occurrence area. It is configured by a display unit 32 as a notification unit for displaying and an operation unit 33 provided with various switches such as a recovery switch and a test switch.

FIG. 2 shows a plurality of fire detectors DE provided on the ceiling 1 or the ceiling 3 in another embodiment of the fire detection device, based on the operation information of the air conditioning equipment AC at the place where these are installed. The fire determination means FG in the fire detector DE is configured to switch the fire determination standard.

That is, the fire detector DE is composed of, for example, a photoelectric smoke detector, a fire phenomenon detection means 21, and a fire phenomenon detection means.
Fire discrimination means FG for discriminating whether or not there is a fire by comparing the output of 21 with the fire discrimination standard, receiving means 24 for receiving, for example, the ventilation frequency as the operating condition of the air conditioning equipment AC, and receiving means.
The output of 24 is composed of, for example, a switching unit 25 for switching the reference voltage as the fire determination reference of the fire determination unit FG, and the fire determination unit FG is the output of the fire determination unit 22 and the fire determination unit 22. It is configured by a fire signal transmission unit 23 that sends information on the occurrence of a fire to the fire receiver RE.

The fire receiver RE is a fire signal receiving unit that receives a fire signal.
31, a display unit as a notifying means 32 for notifying the output of the fire signal receiving unit 31, and an operation unit 33 provided with various switches such as a recovery switch and a test switch.

The function of the fire discriminating means FG of the fire detector DE in the embodiment of FIG. 2 is similar to that after the step of the flow chart of FIG. 6 described below.

The function of the fire discriminating means 36 will be described with reference to the flow chart of FIG.

This figure has N fire sensor SE, and shows a case of setting three fires as a fire discrimination reference determination level L _1, L _2, L _3, the specific values of L ₁ ~L ₃ An example is as shown in FIG.

First, initial values such as the fire discrimination levels L _{1 to} L ₃ are set (step), and the detection output V is read from the first fire sensor (step).

Next, the ventilation frequency K of the air conditioning equipment AC at the installation location of the first fire sensor is read (step), and the fire discrimination means 36 determines whether or not there is a fire based on the value of this K (step ~).

(A) When the fire sensor SE is provided on the ceiling 1.

When the air conditioning equipment AC is stopped, that is, when K = 0 (step), if the detection output V is L ₁ = 10% / m or more, it is determined that a fire has occurred (step), and the fire area is displayed. This is performed by the notification means 32 as a display unit.

If K ≠ 0 in step, the fire discrimination level L ₂ or L ₃ is selected depending on the magnitude of the ventilation frequency.

If the detection output V shows L ₂ = 8 or more when the ventilation frequency K is less than 3 (step,), it is determined that a fire has occurred, and in the high-speed operation when the ventilation frequency K is 3 or more, the detection output V is L ₃ = 6
From the above, it is judged that a fire has occurred.

As described above, in the case where the fire sensor SE is provided on the ceiling 1, the switching means is arranged to switch the fire determination means 36 to the higher sensitivity side as the number of ventilations of the air conditioning equipment AC increases.
25 are made up.

(B) When the fire sensor SE is provided in the attic 3

When the air conditioning equipment AC is stopped, the detection output V is L ₁
= 6% / m or more, it is judged that a fire has occurred (step), and when the air conditioning equipment AC is operating, if the detection output V shows L ₂ = 8 or more when the ventilation frequency K is less than 3, a fire occurs. Therefore, in high-speed operation where the ventilation rate K is 3 or more, the detection output V becomes L ₃ = 10 or more and it is determined that a fire has occurred.

As described above, in the case where the fire sensor SE is provided on the ceiling 3, the switching means 25 is configured to switch the fire determination means 36 to the low sensitivity side as the number of ventilation of the air conditioning equipment AC increases. Has been done.

(Effects of the Invention) As described above, the fire detection device according to the present invention has a fire discrimination means having a plurality of fire discrimination criteria for discriminating a fire by the output of the fire phenomenon detection means, and a fire occurrence by the output of the fire discrimination means. Since it has a notifying means for notifying, a receiving means for receiving the operation information of the air conditioning equipment, and a switching means for switching the fire discrimination standard of the fire discrimination means by the output of the reception means, the fire is constituted. For example, when the detection means is installed indoors and the number of ventilations by the air conditioning equipment is high, the smoke from the fire is diffused and diluted, and when the smoke concentration near the installation position of the fire detection means becomes low, the air conditioning equipment is installed. From this, the ventilation frequency is input as operation information to the switching means via the receiving means, and the switching means switches the fire discrimination standard of the fire discrimination means to the high-sensitivity side. Without reliable fire alarm is performed.

In this way, the fire discrimination standard can be appropriately switched in response to changes in the diffusion and dilution of fire smoke depending on the operating conditions of the air conditioning equipment, resulting in unreported, delayed or misreported information. Without that, the fire information will be promptly and reliably provided.

In the invention in which the fire phenomenon detecting means is provided in the room, the switching means is configured to switch the fire determination standard of the fire determining means to a highly sensitive side in accordance with an increase in the ventilation frequency, or In the case where the fire phenomenon detection means is provided in the plenum chamber at the back of the ceiling, the switching means is configured to switch the fire discrimination standard of the fire discrimination means to the low sensitivity side as the ventilation frequency increases. The invention of an aspect has an advantage that a fire alarm can be promptly and surely performed when the fire phenomenon detection means is provided on the lower surface of the ceiling or when the fire phenomenon detection means is provided on the back side of the ceiling. Have

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, FIGS. 1 and 2 are block diagrams of a fire detection device showing the respective embodiments of the present invention, FIG. 3 is a plan view of a chamber used in an experiment, and FIG. Is a front view in the modeled state of FIG. 3, FIG. 5 is experimental data, FIG. 6 is a flow chart of the switching means, and FIG. 7 is fire discrimination level data. 1 ... Ceiling, 2 ... Slab, 3 ... Attic, 4 ... Partition, 5 ... Air inlet, 6 ... Air outlet, 7 ... Indoor, 8
...... Control valve, 9 ...... Exhaust pipe, 10 ...... Control valve, 21 ...... Fire phenomenon detection means, 22 ...... Fire discrimination section, 23 ...... Fire signal transmission section, 24 ...... Reception means, 25 ...... Switching Means, 26 ... A / D converter, 27 ... Signal processing section, 28 ... Transmission / reception circuit, 31 ... Fire signal reception section, 32 ... Notification means, 33 ... Operation section, 34 ... Transmission / reception section, 35 …… Reception circuit, 36, FG …… Fire discrimination means, AC
...... Air conditioner, DE, P, S …… Fire detector, RE …… Fire receiver, SE …… Fire sensor,

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hidenori Miyamoto, 4-7-3 Kudan-minami, Chiyoda-ku, Tokyo Within Nomi Disaster Prevention Industry Co., Ltd. (72) Koji Tanaka 4--7-3, Kudanminami, Chiyoda-ku, Tokyo Nomi Disaster Prevention Industry Co., Ltd.

Claims (6)

(57) [Claims] 1. A fire discriminating means having a plurality of fire discrimination criteria for discriminating a fire by the output of the fire phenomenon detecting means, and a notifying means for notifying the occurrence of a fire by the output of the fire discriminating means.
A fire detection device comprising: a receiving means for receiving operation information of the air conditioning equipment; and a switching means for switching a fire discrimination reference of the fire discrimination means by an output of the receiving means. 2. The fire detecting device comprises a fire detector having a fire phenomenon detecting means, a fire determining means, a receiving means, a switching means, and a fire receiver having an informing means. The fire detection device according to claim 1, which is characterized by the above-mentioned. 3. The fire detecting device comprises a fire sensor having a fire phenomenon detecting means, a fire judging means, a receiving means, a switching means, and a notifying means. The fire detection device according to claim 1. 4. The fire phenomenon detecting means includes a fire phenomenon detecting section,
The fire detection device according to claim 1 or 3, further comprising an A / D converter and a transmission / reception unit. 5. When the fire phenomenon detection means is provided indoors, the switching means is switched to a highly sensitive side of the fire discrimination standard of the fire discrimination means as the number of ventilations by the air conditioning equipment increases. The fire detection device according to claim 1, 2 or 3, wherein the fire detection device is configured as described above. 6. When the fire phenomenon detecting means is provided in the plenum yard at the back of the ceiling, the switching means is set to a low sensitivity side, which is one of the fire judging standards of the fire judging means, as the number of ventilations by the air conditioning equipment increases. The fire detection device according to claim 1, 2 or 3, wherein the fire detection device is configured to be switched to.