JP3222743B2 - Fire detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a system ceiling T
The present invention relates to a fire detector attached to an air conditioning inlet such as a bar slit.

[0002]

2. Description of the Related Art Conventionally, as this type of fire detector installed in a T-bar slit on a system ceiling, for example, the one shown in FIGS.
No. 57163). 8 and 9, reference numeral 101 denotes a housing of a fire detector, and the housing 101 includes T-bars 102 and 1.
03 is mounted on flanges 102a and 103a. An exhaust gap 104 is formed between the flange 102a and the flange 103a, and air is sucked in from the exhaust gap 104 by an air adjusting device to perform air conditioning. Case 10
1 includes a fire detection unit 105 and a circuit component storage unit 1.
06 is provided. A protrusion 108 is formed on the bottom wall 107 of the housing 101, and air inlets 109 and 110 are formed on the peripheral side wall and the bottom wall of the protrusion 108. Also,
Air outlets 112 and 113 are formed on the top wall 111 of the housing 101 just above the fire event detection unit 105 and on both side walls. A plurality of lower passage forming walls 114 that form labyrinth passages for blocking external light are arranged between the air inlet 110 and the fire phenomenon detection unit 105,
In addition, a plurality of upper passage forming walls 115 that form labyrinth passages for blocking external light are arranged between the air outlet 112 and the fire phenomenon detection unit 105. The fire phenomenon detection unit 105 is configured as a dark box surrounded by the lower passage forming wall 114, the upper passage forming wall 115, and the inner wall of the housing 101, and a light projecting element 116 and a light receiving element 117 are provided in the dark box. I have.

[0003] Now, when a fire occurs indoors, combustion products (hereinafter referred to as smoke) rise in an updraft due to heat generated at the time of the fire and are sucked into the exhaust gap 104 in the system ceiling. The smoke rising toward the exhaust gap 104 directly flows into the air inlets 109 and 110 without resistance, passes through the labyrinth passage formed by the lower passage forming wall 114, and passes through the fire detection unit 105. It flows into a certain dark box. The smoke that has flowed into the dark box further rises and passes through the labyrinth passage formed by the upper passage-forming wall 115 and flows out of the system ceiling from the air outlets 112 and 113. Since the smoke is forcibly and continuously sucked into the exhaust gap 104, the inflow of the smoke into the dark box is also performed continuously. On the other hand, the light projecting element 116 in the dark box is periodically pulsed. Then, the light projected from the light emitting element 116 is scattered by the inflowing smoke, and the light receiving element 117 detects the scattered light. The detection signal of the light receiving element 117 is amplified, and when the smoke density exceeds the set value, the switching circuit is operated. The output of the switching circuit is the lead 11
A fire detector sent to a receiver (not shown) via the display unit 8 is displayed, and an alarm is sounded to notify the occurrence of a fire.

[0004] The fire detector is attached to the exhaust gap 104, and forcibly introduces smoke into the fire phenomenon detection unit 105 by suction pressure of an air conditioner.

[0005]

However, in such a conventional fire detector, when the air conditioner is stopped, not only is it not possible to obtain the effect of introducing smoke by suction, but also due to some cause from the air conditioning duct. When the backflow of the air occurs, there is a problem that the discharged air pressure hinders the inflow of smoke into the detector main body at the time of fire and the fire cannot be quickly detected.

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional problem, and prevents the inflow of smoke into the main body of the sensor even if there is a backflow of air from the duct due to some cause when air conditioning is stopped. An object of the present invention is to provide a fire detector capable of performing fire detection quickly without being detected.

[0007]

In order to achieve the above object, the present invention is configured as follows. First, the present invention provides a fire detector which is attached to a suction port of an air conditioner opened in a slit shape on a system ceiling and forcibly introduces smoke into a sensor main body by using a suction pressure of the air conditioner. set to target.

The present invention relates to such a fire detector,
The sensor main body behind the ceiling has an inlet for smoke in the monitoring area below the ceiling surface, which is provided in the sensor body, and an inlet for introducing airflow from the air conditioner, and an outlet for extracting airflow from the ceiling. A passage in the sensor body on the back side,
A restrictor provided in the middle of the passage to increase the flow velocity of the introduced airflow, a discharge opening which opens into the restrictor and discharges the smoke flowing in from the inlet into the passage , and between the inlet and the discharge Established in
And a smoke detector for detecting smoke .

In the present invention, the inlet is formed on the side of the sensor body behind the ceiling, and the outlet is formed on the upper surface of the sensor body. Further, the present invention provides a slit formed in the ceiling of the system at the lower end of a protrusion protruding laterally from the sensor body behind the ceiling, and the outlet is formed at the upper end of the protrusion above the inlet. Formed.

Further, the present invention relates to a fire detector which is attached to a suction port of an air conditioner and forcibly introduces smoke into the sensor body by using a suction pressure of the air conditioner. An inflow port provided at a position protruding below the ceiling surface of the main body, through which smoke flows in, a discharge port provided at the top of the sensor body on the back side of the ceiling to discharge smoke, and smoke is discharged from the discharge port and the inflow port. A check valve provided between the smoke detector to be detected, the vent opening being opened by suction pressure, and closing the vent by reverse flow of airflow from the outlet.

[0011] The check valve of the present invention has a hinge mechanism for opening a vent by suction pressure. In addition, the check valve of the present invention is formed of a flexible material that opens a vent by suction pressure. In the present invention, the check valve is always open when the air conditioner is stopped and when there is no wind.

Further, in the present invention, a small fan which operates when the air conditioner is stopped and blows air to the check valve to open the vent is provided in the sensor body. According to the fire detector of the present invention having such a configuration, the inlet provided for the detector body projecting below the ceiling surface into which smoke flows in, and the inlet for introducing airflow by the air conditioner are provided. A passage having a sensor body behind the ceiling and having an outlet for guiding the airflow in the sensor body behind the ceiling, a restrictor provided in the middle of the passage to increase the flow velocity of the introduced airflow, and an opening in the restrictor. A discharge port for discharging the smoke flowing in from the inflow port, the inlet is formed on the side of the sensor body behind the ceiling, and the outlet is formed on the upper surface of the sensor body, so when the air adjusting device is operated, Smoke can be introduced into the main body of the sensor by the suction pressure for quick fire detection, and even when the air conditioner is stopped and there is a backflow of airflow from the air conditioning duct, the smoke flows into the main body of the sensor Quick fire without disturbing Sensing can be performed.

In the case where the inlet is formed at the lower end of a protrusion protruding laterally from the sensor body behind the ceiling and the outlet is formed at the upper end of the protrusion above the inlet, The introduction is easy, and the effect of introducing smoke from the inlet can be enhanced. In addition, an inflow port provided in the sensor body projecting below the ceiling surface into which smoke flows in, a discharge port provided in the upper part of the sensor body on the back side of the ceiling to discharge smoke, and a discharge port and an inflow port. A check valve provided between the smoke detector for detecting smoke and opening the ventilation port by suction pressure and closing the ventilation port by reverse flow of the airflow from the discharge port. During operation, smoke can be introduced into the sensor body by suction pressure to quickly detect fire, and even when the air conditioner is stopped and there is a backflow of airflow from the air conditioning duct, the smoke detector body A quick fire detection can be performed without obstructing the inflow into the inside.

Further, since the check valve has a hinge mechanism for opening the vent by suction pressure, the vent can be opened and closed with a simple structure. In addition, since the check valve is formed of a flexible material that opens the ventilation port by suction pressure, the ventilation port can be opened and closed with a simple configuration. In addition, the check valve is always open when the air conditioner is stopped and there is no wind, so it is necessary to help the smoke flow into the sensor body even when there is no backflow of airflow. Can be.

Further, since a small fan that operates when the air conditioner is stopped and blows air to the check valve to open the ventilation hole is provided in the sensor body, it is possible to prevent smoke from flowing into the sensor body even when there is no wind. I can help.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing a state where a fire detector according to the present invention is mounted on a ceiling, and FIG. 2 is a perspective view of the mounting. 1 and 2, reference numeral 1 denotes a ceiling, and the ceiling 1
Are formed with a plurality of air conditioning inlets 2 such as T-bar slits.

A sensor main body 3 of a fire detector is attached to the air-conditioning inlet 2, and a lower part of the sensor main body 3 is provided at the air-conditioning inlet 2.
From the ceiling surface 4 below. An inflow port 6 for inflow of smoke is formed in a lower bottom wall of the sensor main body 3 protruding below the ceiling surface 4. Here, the sensor main body 3 protrudes below the ceiling surface 4, but is not limited thereto, and the sensor main body 3 may be provided so as to enter the ceiling surface 4. The inflow port 5 may be formed not only on the lower bottom wall of the sensor body 3 but also on the lower side wall. In the sensor main body 3 above the ceiling surface 6, a smoke detection unit 7 for detecting smoke flowing from the inflow port 5 and a circuit board (not shown) are provided. A light-emitting element and a light-receiving element (not shown) are provided in the smoke detector 7. When light emitted from the light-emitting element is scattered by smoke flowing into the smoke detector 7, the light-receiving element detects the scattered light. I do.

A light emitting element, a light receiving element, a light emitting circuit, an amplifier circuit, a switching circuit, etc. are mounted on a circuit board, and a power supply line and a signal line of the light emitting element and the light receiving element are connected to the circuit board. These power lines and signal lines are connected to power lines and signal lines for fire alarm equipment provided behind the ceiling 1 via a connector or the like. A pair of inlets 8 and 9 for introducing an air flow by an air adjusting device are formed on the side surface of the sensor main body 3, respectively, and the air adjusting device introduced from the inlets 8 and 9 is provided on the upper surface of the sensor main body 3. A pair of outlets 10 and 11 for extracting an airflow are formed respectively.

The inlets 8 and 9 and the outlets 10 and 11 communicate with each other through a pair of passages 12 and 13, and in the middle of the passages 12 and 13, a throttle unit for increasing the flow velocity of the air flow introduced from the inlets 8 and 9. 14 and 15 are formed. The opening areas of the passages 12 and 13 from the inlets 8 and 9 to the throttles 14 and 15 gradually decrease, and the outlets 10 and 1 extend from the throttles 14 and 15.
The opening areas of the passages 12 and 13 up to 1 are formed so as to gradually increase.

During operation of the air conditioner, the air flow sucked into the air-conditioning suction port 2 from the room 16 below the ceiling surface 4 is introduced from the introduction ports 8 and 9, and the flow velocity is increased at the throttle portions 14 and 15. After that, it is discharged from the outlets 10 and 11 to the space above the ceiling. Conversely, when the air conditioner is stopped, there is a backflow from the air conditioning duct for some reason, and when air is discharged from behind the ceiling into the room 16, the airflow is introduced from the outlets 10 and 11, and , 15 are discharged from the inlets 8 and 9 after the flow rate is increased.

A space 17 is formed above the smoke detector 7,
The smoke flowing from the inflow port 5 is introduced into the space 17 through the smoke detector 13. Discharge ports 18 and 19 are formed in the space 17, and the discharge ports 18 and 19 are
4 and 15 respectively. Therefore, the air flowing from the inflow port 5 is introduced into the space 17 through the smoke detector 7 by the suction pressure of the air adjusting device, and
It is discharged from outlets 10 and 11 from passages 8 and 19 through passages 12 and 13. In addition, when the air conditioner is stopped, there is a backflow from the air-conditioning duct for some reason, and when air is discharged from the ceiling surface into the room 16, the airflow is introduced from the outlets 10 and 11, and the throttles 14 and 15. Is discharged from the inlets 8 and 9 at an increased speed. In this case, the sensor body provided below the ceiling surface 6 and provided above the ceiling surface 6 above the pressure of the inflow port 5 of the sensor body 3 3 outlets 1
Since the pressures at 8 and 19 are lower, the smoke detector 7
The smoke introduced into the space 17 via the outlets is discharged from the outlets 18 and 19 and discharged from the inlets 8 and 9.

That is, comparing the pressure of the inflow port 5 with the pressure of the discharge ports 18 and 19 provided in the throttle sections 14 and 15, the throttle section 1
As an effect of the airflow acceleration of the airflows 4 and 15, the pressures at the discharge ports 18 and 19 are lower than the pressure at the inlet 5 by Bernoulli's theorem. According to Bernoulli's theorem, for a steady flow of a viscous liquid that does not shrink, the following equation holds. _{v 2/2 + P / ρ} + gz = constant v is velocity, P is pressure, [rho is the density, g is the gravitational acceleration, z
V ₁ ^2, P ₁ pressure arbitrary height from the horizontal plane thus, the flow velocity in the inlet 5 there is
Assuming that the flow velocity at the discharge ports 18 and 19 is v ₂ ² and the flow velocity is P ₂ , the following equation is established. ^{_{v 1 2 / + P 1 /}} ρ = v 2/2 + P 2 / ρ v 1 < because it is v _2, P _1> According to P ₂ Bernoulli's principle, the pressure of the liquid decreases as the flow rate increases.

For this reason, regardless of the operation or stoppage of the air conditioner, smoke is always discharged from the inlet 5 through the smoke detector and the discharge ports 18 and 19 through the space 17. Next, the operation will be described. First, the operation at the time of operating the air conditioner will be described. During the operation of the air conditioner, the air in the room 16 is sucked into the back of the ceiling from the air-conditioning suction port 2 by the suction pressure, and a part of the air is introduced into the inlets 8 and 9 and the throttle sections 14 and 1 are drawn.
After the flow velocity is increased at 5, the liquid is discharged from the outlets 10 and 11.

Further, the air in the room 16 flows into the inflow port 5 by the suction pressure of the air conditioner, and flows into the smoke detector 7 and the space 17.
And enters the passages 12 and 13 from the discharge ports 18 and 19 through the outlets 10 and 11. Now, when a fire occurs in the room 16, the smoke rises due to the rising airflow due to the heat at the time of the fire, and is sucked from the air-conditioning suction port 2 to the back of the ceiling and flows into the inflow port 5 of the sensor body 3. Then, enter the smoke detection section 7. Smoke forcibly and continuously flows into the inflow port 5 by the suction pressure of the air adjusting device, and the inflow of smoke to the smoke detection section 7 is also continuously performed. The light emitting element provided in the smoke detecting section 7 is periodically pulse-lighted, the light projected from the light emitting element is scattered by the inflowing smoke, and the light receiving element detects the scattered light. The detection signal of the light-receiving element is amplified, and when the smoke concentration exceeds the set value, the switching circuit operates, and the output of the switching circuit is sent to a receiver (not shown) to display the fire area and to indicate the occurrence of a fire with a bell or the like. Alarm.

On the other hand, the smoke that has passed through the smoke detector 7 enters the space 17, is discharged from the discharge ports 18 and 19 to the passages 12 and 13, and is discharged from the discharge ports 10 and 11. As described above, when the air conditioner operates, smoke is forcibly introduced into the sensor main body 3 by the suction pressure, so that quick fire detection can be performed. Next, the operation of the air conditioner when it is stopped will be described.

When the air conditioner is stopped, if there is a backflow of the airflow from the air duct for some reason, and the air is discharged into the room 16 from above the ceiling, the airflow flows from the air conditioning suction port 2 into the room 16. While being introduced from the outlets 10 and 11 and the constrictions 14 and 15
After the flow velocity is increased by the above, the gas is discharged from the inlets 8 and 9.
Here, when a fire occurs in the room 16, the smoke rises due to the rising airflow caused by the heat at the time of the fire and flows into the inlet 5. The smoke that has flowed into the inflow port 5 passes through the smoke detection section 7 to the space 17.
Into the outlets 18 and 19, and comparing the pressure at the inlet 5 with the pressure at the outlets 18 and 19,
The pressure at the discharge ports 18 and 19 becomes lower than the pressure at the inflow port 5 by Bernoulli's theorem as an effect of the airflow acceleration at 15. For this reason, the smoke is discharged from the inlet 5 through the smoke detector 7, the space 17, and the outlets 18 and 19, and is discharged from the inlets 8 and 9. As described above, when the air conditioner is stopped, the airflow flows from the outlets 10 and 11 to the inlets 8 and
Even when the air flows backward, the pressure at the outlets 18 and 19 becomes lower than that of the inlet 5 due to the acceleration of the airflow by the throttles 14 and 15, so that the inflow of smoke into the smoke detector 7 is limited. Without the need for quick fire detection.

When there is no airflow when the air conditioner is stopped, the smoke flowing into the inlet 5 due to the specific gravity of the smoke rises as it is, passes through the smoke detector 7, the space 17 and the outlet 18 , 19, and is discharged from outlets 10, 11 through passages 12, 13. Therefore, regardless of the operation or stoppage of the air conditioner, quick fire detection can be performed.

FIG. 3 is a diagram showing another embodiment of the present invention. In FIG. 3, an air-conditioning suction port 2 through which air is sucked by an air conditioner is formed in a ceiling 1, and a fire detector main body 3 is inserted into the air-conditioning suction port 2. The sensor main body 3 protruding into the room 16 below the ceiling surface 4 is formed with an inflow port 5 through which smoke flows. Further, inside the sensor body 3 above the ceiling surface 6 above the ceiling surface 6, a smoke detection section 7 for smoke flowing from the inflow port 5 and a circuit board (not shown) are stored. Above the smoke detector 7, a space 17 into which smoke flowing in from the inflow port 5 is introduced through the smoke detector 7 is formed.

On the upper side of the sensor main body 3, a projecting portion 20 protruding laterally from the sensor main body 3 is formed. Inlet ports 8 and 9 for introducing an air flow by the air conditioner are formed on the lower end face of the protruding part 20, respectively, and the inlet ports 8 and 9 are provided on the upper end face of the protruding part 20 just above the inlet ports 8 and 9 respectively. Outlet ports 10 and 11 for deriving the more introduced airflow are formed respectively. The inlets 8 and 9 communicate with the outlets 10 and 11 by passages 12 and 13, and throttles 14 and 15 are formed in the passages 12 and 13. Aperture part 1
4 and 15 increase the flow velocity of the airflow introduced from the inlets 8 and 9. Passage 1 from inlets 8 and 9 to constrictions 14 and 15
The opening areas of the apertures 2 and 13 gradually become smaller,
The opening areas of the passages 12, 13 from 15 to the outlets 10, 11 are formed so as to gradually increase. Discharge ports 18 and 19 are opened in the throttle portions 14 and 15, respectively, and the passages 12 and 13 communicate with the space 17 through the discharge ports 18 and 19. Since airflow acceleration occurs in the throttle portions 14 and 15, the discharge ports 18 and 19 are obtained according to Bernoulli's theorem.
Is lower than the pressure at the inlet 5. Therefore, when the air conditioner is stopped, there is a backflow of the airflow from the air conditioning duct for some reason, and the airflow is introduced from the outlets 10 and 11 as shown by arrows a, and the inlets 8 and 9
Even when the smoke is discharged, the smoke flowing in from the inflow port 5 remains in the smoke detector 7 and the space 17 as shown by arrows b, c and d.
Through the outlets 18 and 19 and the inlets 10 and 1
Emitted from 1. When operating the air conditioner,
Due to the suction pressure, the smoke flowing into the inflow port 5 is discharged from the discharge ports 18 and 19 through the smoke detection section 7 and the space 17, and is discharged from the discharge port 1.
Emitted from 0,11. If there is no airflow when the air conditioner is stopped, the smoke flowing into the inlet 5 due to the specific gravity of the smoke passes through the smoke detector 7, the space 17, and the outlet 18,
It is discharged from 19 and discharged from outlets 10 and 11.
Therefore, regardless of the operation or stoppage of the air conditioner, quick fire detection can be performed.

In the present embodiment, a protrusion 20 is provided on the upper side of the sensor body 3 to protrude laterally, and inlets 8, 9 are formed on the lower end surface of the protrusion 20. Since the outlets 10 and 11 are formed on the upper end surface of the protruding portion 20 immediately above, the introduction of the airflow is facilitated, and the smoke introduction effect of introducing the smoke from the inflow port 5 to the smoke detector 7 can be enhanced. next,
FIG. 4 is a sectional view showing another embodiment of the present invention.

In FIG. 4, reference numeral 1 denotes a ceiling, and the ceiling 1 is provided with an air-conditioning suction port 2 for sucking air by an air conditioner. The main body 3 of the fire detector is attached to the air-conditioning inlet 2 and the room 1 below the ceiling surface 4
The sensor main body 3 protruding into 6 has an inlet 5 for inflow of smoke. Inside the sensor body 3 above the ceiling surface 6 and behind the ceiling, a smoke detection section 7 for detecting smoke flowing from the inflow port 5 and a circuit board 21 are provided. Smoke detector 7
A light projecting element 22 and a light receiving element 23 are provided therein, and the light projected from the light projecting element 22 is scattered by the inflowing smoke, and the light receiving element 23 receives the scattered light. The light emitting element 22 and the light receiving element 23 are mounted on a circuit board 21, and a light emitting circuit, an amplifier circuit, a switching circuit and the like are mounted on the circuit board 21, and a discharge port 24 is formed on an upper side wall of the sensor body 3. A check valve 25 is swingably provided between the discharge port 24 and the smoke detection section 7. Check valve 2
Numeral 5 has a hinge function, and opens the vent 27 of the passage 26 leading from the smoke detector 7 to the discharge port 24 when the air adjusting device operates, and closes the vent 27 by its own weight or reverse airflow when the air adjusting device stops. The check valve 25 is swingably attached to a projection 28 projecting downward from the upper wall of the sensor main body 3 via an attachment portion 29.

During the operation of the air conditioner, the check valve 24 opens the ventilation port 27 by the suction pressure, and the smoke flowing into the inflow port 5 passes through the smoke detection section 7 and passes from the smoke detection section 7 to the discharge port 24. Is discharged from the discharge port 24 through a passage 26 leading to As described above, when the air conditioner operates, the fire can be quickly detected by forcibly introducing smoke into the sensor main body 3 by the suction pressure. When the air conditioner is stopped, the check valve 25 closes the ventilation port 27 by its own weight or an airflow flowing backward from the air conditioning duct. This can prevent the backflow of the airflow from the discharge port 24 from entering the smoke detection section 7. Therefore, when a fire occurs, it is possible to detect the fire quickly without hindering the flow of the smoke from the inflow port 5 into the smoke detection section 7.

As shown in FIG. 5, the check valve may be formed of a flexible material such as a vinyl piece, and may be curved by its elasticity to open the ventilation port 27. Check valve 2
One end of 5 </ b> A is fixed to the tip of the protruding portion 28 by a screw 30 or the like, and the other end extends on the tip of the circuit board 21. During the operation of the air conditioner, the check valve 25A bends to open the ventilation hole 27 formed between the protrusion 28 and the circuit board 21 by the suction pressure. When the air conditioner is stopped, the check valve 25A closes the vent 27 by its own weight or an airflow flowing backward from the air conditioning duct.

If there is no backflow of the airflow from the air conditioning duct even when the air conditioner is stopped, the check valve 25 is opened to help the smoke to flow into the smoke detector 7 due to the rise of the smoke. It is desirable to open a passage 26 from the smoke detector 7 to the discharge port 24. For this reason, in FIG. 6A (A), the vent 27 is opened by the check valve 25B when there is no wind, and the vent 27 is closed by the check valve 25B when the airflow is reverse.

One end of the check valve 25B is fixed to the tip of the circuit board 21, and the other end is a free end. Check valve 25
B is formed of a flexible material. When the air conditioner is stopped and when there is no wind as shown in FIG. 6 (A), the check valve 25B is connected to the ventilation port 2 between the projection 28 and the circuit board 21.
Since the opening 7 is open, the smoke flowing into the inflow port 5 is discharged from the discharge port 24 through the ventilation port 27 as shown by an arrow e. Therefore, it is possible to perform quick fire detection without hindering the flow of smoke into the smoke detection section 7. Also, when the air conditioner is stopped and the airflow is backflowing, the check valve 25B bends due to the airflow indicated by the arrow f and closes the ventilation port 27. Therefore, even if there is a reverse flow of the airflow from the air conditioning duct, the flow of smoke into the smoke detection section 7 is not hindered, and quick fire detection can be performed.

FIG. 7 is a diagram showing another embodiment of the present invention. In FIG. 7, reference numeral 31 denotes a small fan provided on the front surface of the check valve 25. The small fan 31 operates when the air conditioner stops, and opens the check valve 25. Therefore, when the air conditioner is stopped and there is no wind in which there is no backflow from the air conditioning duct, the vent 27 is opened to help the smoke to flow into the smoke detection section 7. Also, even if there is a backflow from the air conditioning duct, the check valve 25 is forcibly opened,
Smoke was allowed to flow into the smoke detector 7. The small fan 31 is driven by a motor 27, and the motor 2 is attached to the smoke detector 7 or the upper wall of the sensor main body 3. In the present embodiment, smoke can be introduced into the smoke detector 7 particularly when there is no wind when the air conditioner is stopped.

[0037]

As described above, according to the present invention, when the air conditioner operates, smoke can be introduced into the main body of the sensor by suction pressure, thereby enabling quick fire detection. Even when the air conditioner is stopped and there is a backflow of airflow from the air conditioning duct, or even when there is no wind, it is possible to quickly detect a fire without preventing the inflow of smoke into the detector main body.

[Brief description of the drawings]

FIG. 1 is a view showing a state where a fire detector according to the present invention is mounted on a ceiling.

FIG. 2 is a perspective view of mounting.

FIG. 3 is a diagram showing another embodiment of the present invention.

FIG. 4 is a diagram showing another embodiment of the present invention.

FIG. 5 is a diagram illustrating the operation of a check valve.

FIG. 6 is a diagram illustrating the operation of another check valve.

FIG. 7 shows another embodiment of the present invention.

FIG. 8 shows a conventional example.

FIG. 9 is another sectional view showing a conventional example.

[Explanation of symbols]

 1: Ceiling 2: Air conditioning inlet 3: Sensor main body 4, 6: Ceiling surface 5: Inlet 7: Smoke detector 8, 9: Inlet 10, 11: Outlet 12, 13: Passage 14, 15: Restrictor Part 16: Room 17: Space 18, 19: Discharge port 20: Projection 21: Circuit board 22: Light emitting element 23: Light receiving element 24: Discharge port 25, 25A: Check valve 26: Passage 27: Vent 28: Projecting part 29: Mounting part 30: Screw 31: Small fan 32: Motor

Claims (8)

(57) [Claims] 1. A fire which is attached to a suction port of an air conditioner opened in a slit shape on a ceiling of a system and detects smoke by forcibly introducing smoke into a sensor body using suction pressure of the air conditioner. In the sensor, an inflow port provided in the sensor main body and through which smoke in a monitoring area below a ceiling surface flows, and an inlet for introducing an air flow by the air conditioner is provided in the sensor main body behind the ceiling. A passage having an outlet for guiding the airflow in the sensor body behind the ceiling, a throttle provided in the middle of the passage to increase the flow velocity of the introduced airflow, and an opening in the throttle and opening from the inlet. The inflowing smoke passes through the passage
A discharge port for discharging to the side, and smoke for detecting smoke provided between the inflow port and the discharge port.
Fire detector characterized by comprising a detection unit. 2. The fire detector according to claim 1, wherein the inlet is formed on a side surface of the sensor body behind the ceiling, and the outlet is formed on an upper surface of the sensor body. Features a fire detector. 3. The fire detector according to claim 1, wherein the introduction port is formed at a lower end of a protrusion protruding laterally from the sensor main body behind the ceiling, and the outlet port is provided with the introduction port. A fire detector formed at the upper end of a protruding portion above a mouth. 4. A fire sensor which is attached to a suction port of an air conditioner which is opened in a slit shape on a system ceiling and forcibly introduces smoke into a sensor body using a suction pressure of the air conditioner. An inflow port provided at a position protruding below the ceiling surface of the sensor main body to flow in smoke, and a discharge port provided at an upper portion of the sensor main body on the back side of the ceiling to discharge smoke. A check valve provided between a discharge port and a smoke detection section for detecting smoke from the inflow port, the check valve being configured to open a ventilation port by the suction pressure and close the ventilation port by a reverse flow of an airflow from the discharge port. A fire detector. 5. The fire detector according to claim 4, wherein said check valve has a hinge mechanism for opening said vent with said suction pressure. 6. The fire detector according to claim 4, wherein the check valve is formed of a flexible material that opens the ventilation port with the suction pressure. 7. The fire detector according to claim 4, wherein the check valve is always open when the air conditioner is stopped and when there is no wind. And fire detector. 8. The fire sensor according to claim 4, wherein a small fan that is activated when the air conditioner is stopped and blows the check valve to open the ventilation port is provided in the sensor body. A fire detector.