JPH0636158A - Ultrasonic type fire detector - Google Patents

Abstract

PURPOSE:To detect over a wide area, using an ultrasonic switch. CONSTITUTION:The transmitting and receiving wave detection sensor 3 of a reflector type ultrasonic switch is installed at the position near a ceiling surface 1A of one side wall 1B of a room 1. By this transmitting and receiving wave detection sensor 3, ultrasonic wave to be transmitted and received is made to advance in parallel with the ceiling surface 1A, the temperature change of air in the advancing route of ultrasonic wave is detected or the deflection of the advancing direction of ultrasonic wave due to the temperature gradient of air of the advancing route is detected, and an abnormal alarm is given.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elapsed time until an ultrasonic wave pulse is transmitted by an ultrasonic wave oscillator and the ultrasonic wave pulse is received by a receiving portion arranged facing the ultrasonic wave oscillator. An ultrasonic switch that detects the distance from the ultrasonic transducer to the receiving unit by this measurement data and outputs a switch output that determines whether or not the detection object is within a distance range set from the outside, or The ultrasonic transducer transmits an ultrasonic pulse, and the elapsed time until the ultrasonic pulse is received by the receiving unit arranged facing the ultrasonic transducer is measured. Ultrasonic fire detection device that uses an ultrasonic switch that detects the distance from the vibrator to the receiving unit and determines whether or not this distance is within the distance range set from the outside

[0002]

2. Description of the Related Art FIG. 8 is a view showing a state in which a conventional detection sensor is attached to a ceiling surface in a room, (A) is a side view,
(B) is a bottom view of FIG. That is, in this conventional example, four detection sensors 2 are attached to the ceiling surface 1A of the room 1, and the alarm is sounded by detecting a local abnormal temperature rise or smoke. 1B shows the side wall of the room,
The inside of the one-dot chain line indicates the detection area of the detection sensor 2.

[0003]

However, the above-mentioned conventional apparatus can detect only abnormal local room temperature rise and smoke. Therefore, in a large room, a fire away from the detection sensor 2 (outside of the chain line in FIG. 8) may not be detected. In order to solve this, a large number of detection sensors 2 must be installed so that the alternate long and short dash lines in FIG.

The object of the present invention is to solve the above-mentioned problems.
An object of the present invention is to provide a fire detection device that can detect a wide range even if the number of detection sensors is small.

[0005]

According to the present invention, a diffuse reflection type ultrasonic switch is used to change the temperature of air in the path of ultrasonic waves by changing the measured distance data to a detection object placed at a constant distance. Detects and issues an alarm, or detects deflection of the ultrasonic wave in the traveling direction due to the temperature gradient of the air in the ultrasonic path, and issues an alarm. By detecting the change in the temperature of the air on the path of the ultrasonic waves based on the change, the primary alarm is issued, and the deflection in the traveling direction of the ultrasonic wave due to the temperature gradient of the air is detected, and the secondary alarm is issued.

In addition, a transmission type ultrasonic switch is used to detect a temperature change in the air in the ultrasonic wave path due to a change in the measured distance data from the ultrasonic transducer that emits the ultrasonic wave to the receiving section, which causes an abnormality. An alarm is issued, or an abnormal alarm is issued by detecting deflection of the ultrasonic wave in the traveling direction due to the temperature gradient of the air in the ultrasonic path, or the ultrasonic wave is changed by changing the measurement distance data from the ultrasonic transducer to the receiver. The primary warning is issued by detecting the temperature change of the air on the path, and the secondary warning is issued by detecting the deflection of the ultrasonic wave in the traveling direction due to the temperature gradient of the air.

[0007]

[Function] The sound velocity S of ultrasonic waves changes depending on the room temperature.
(° C), the following relationship holds. S = 331.45 + 0.607t (m / s) Further, if there is a temperature gradient in the air, the traveling direction of the ultrasonic waves is bent, and the degree of deflection has the property of increasing as the temperature gradient increases.

Therefore, when the room temperature changes, the detection speed for the equidistant detection object changes. Therefore, if the change is detected, an abnormal alarm is issued, and if there is a temperature gradient, the traveling direction of the emitted ultrasonic wave is bent. The detection sensor, which was transmitting and receiving stably when there is no temperature gradient in the room air, performs unstable detection operation or goes into a non-detection state. In addition, a fire can be detected by catching the former phenomenon and issuing a primary alarm and by catching the latter phenomenon and issuing a secondary alarm.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a case where a diffuse reflection type ultrasonic switch is used, (A) is a side view, (B) is a bottom view taken along the arrow P of (A), and is shown by the same reference numeral as FIG. Are the same part. That is, the wave transmission / reception detection sensor 3 of the diffuse reflection type ultrasonic switch is installed in a state where two wave transmission / reception detection sensors 3 are installed side by side at a position close to the ceiling surface 1A of one side wall 1B of the room 1.
The transmitted and received ultrasonic waves 4 travel parallel to the ceiling surface 1A,
The reflected wave ultrasonic wave 4A also advances and returns to the transmitted / received wave detection sensor 3 in the same manner.

2A and 2B show a case where a transmission type ultrasonic switch is used. FIG. 2A is a side view, FIG. 2B is a bottom view of FIG. It is a part.
That is, the wave transmitter 3A or the wave receiver 3B of the transmission type ultrasonic switch is installed at a position close to the ceiling surface 1A of the one side wall 1B of the room 1, and facing the ceiling surface 1A of the other side wall 1C.
With the wave receiver 3B or the wave transmitter 3A installed at a position close to the ultrasonic wave 4 transmitted from the wave transmitter 3A, the ultrasonic wave 4 is transmitted from the ceiling surface 1A.
The wave travels in parallel with and is received by the wave receiver 3B.

FIG. 3 shows a case where a diffuse reflection type ultrasonic switch is applied to a large room. (A) is a side view, (B) is a view taken in the direction of arrow R of (A), the same as FIG. 1 and FIG. Those denoted by the reference numerals are the same parts. That is, the ceiling surface 1 in the substantially central part of the room
In a state in which the two transmission / reception detection sensors 3 are installed back to back at a position close to A, the transmission / reception ultrasonic waves 4 emitted from the transmission / reception detection sensor 3 travel in parallel to the ceiling surface 1A, and the reflected wave ultrasonic waves 4A The same goes for returning to the wave transmission / reception detection sensor 3.

FIG. 4 shows a case where a transmission type ultrasonic switch is applied to a large room, (A) is a side view and (B) is (A).
In the S arrow view, the same reference numerals as those in FIGS. 1, 2 and 3 are the same parts. That is, the ceiling surface 1 in the substantially central part of the room
The transmission-only detection sensors 3A of the two transmission type ultrasonic switches are installed back to back at a position close to A, and the reception-only detection is made on one side wall 1B and the other side wall 1C facing the transmission-only detection sensor 3A. With the sensor 3B installed, the transmitted / received ultrasonic waves 4 emitted from the wave transmission dedicated detection sensor 3A travel in parallel to the ceiling surface 1A and are received by the wave reception dedicated detection sensor 3B.

Next, a diffuse reflection type ultrasonic switch is used to detect a temperature change in the air in the ultrasonic path by a change in the measured distance data up to a detection object placed at a constant distance, and a preliminary alarm is issued to notify the air temperature. The operation in the case of detecting the deflection of the ultrasonic wave in the traveling direction due to the temperature gradient and issuing an emergency alarm will be described with reference to FIG. Reference numeral 3 denotes a transmission / reception detection sensor of a diffuse reflection type ultrasonic switch, and has a setting A for outputting in the detection areas L _{0 to} L ₁ and a setting B for outputting in the detection areas L _{1 to} L ₂ . 5 is a reflector, in this case the other side wall 1C (see FIG.
(See) may be used instead. When the distance 1 = 5.5 m between the wave transmission / reception detection sensor 3 and the reflector 5 in the room, the setting A of the wave transmission / reception detection sensor 3 is set to L ₁ = 5.3 m, and the setting B is set.
When set to L ₂ = 6 m, put the output setting A under normal conditions.
Is OFF and output setting B is ON. Next, when a situation different from the normal state occurs in the room and the temperature of the ultrasonic path (around 4 in FIG. 1B) rises, the sound velocity of the ultrasonic wave increases, and as shown in FIG. 5.5 (when normal)
The reflector 5 located at a distance of m becomes as if it is at 5.3 m when the temperature of the course reaches 40 ° C., and 1 ≦ L ₁ , and the output setting A changes from ON to OFF, and the output setting B turns OFF.
To ON (initial abnormal condition). When the temperature further rises locally, a large temperature gradient is generated in the path, whereby the reflected wave of the ultrasonic wave emitted by bending the path is not received by the wave transmission / reception detection sensor 3 and l ₂ ≧ L ₂ . The output setting B changes from ON to OFF, and both the output settings A and B become OFF (fire state). This is shown in the table below.

[0014]

[Table 1] That is, when output setting A is OFF and output setting B is ON, an abnormal alarm is issued and both output settings A and B are OFF.
If it becomes, it will function as a fire detection device by issuing a fire alarm.

FIG. 7 is a diagram for explaining the operation when a transmission type ultrasonic switch is used. The parts designated by the same reference numerals as those in FIG. 6 are the same parts. 3A is a detection sensor dedicated to wave transmission and 3B is a detection sensor dedicated to reception. is there. In this case, in the case of the above-mentioned reflection type ultrasonic switch, it is necessary to measure the distance by synchronizing the wave transmission start time of the wave reception dedicated detection sensor 3B with the wave transmission from the wave transmission dedicated detection sensor 3A. Since it operates in the same manner as, the description thereof will be omitted. This is shown in [Table 2] below.

[0016]

[Table 2]

[0017]

According to the present invention, the property that the sound velocity of ultrasonic waves changes due to the temperature change and the property that the traveling direction is deflected when there is a temperature gradient in the course are utilized to make the ceiling surface close to the ceiling surface in the room. It emits ultrasonic waves in parallel, captures changes corresponding to room temperature changes of the emitted ultrasonic waves, or detects deflection of the ultrasonic waves in the traveling direction due to the temperature gradient that occurs in the ultrasonic path, and issues an abnormal alarm. By catching the change corresponding to the room temperature change of the emitted ultrasonic wave, the initial abnormality alarm is issued, and the deflection of the ultrasonic wave in the traveling direction due to the temperature gradient generated in the ultrasonic path is detected and the fire alarm is issued. It can detect abnormal temperature rise in a wide range, and a small number of detectors are sufficient even in a large room. In addition, there is an abnormality (fire) due to the two-stage detection method.
It is effective for early detection of.

[Brief description of drawings]

1A and 1B show a state in which a transmission / reception detection sensor of a diffuse reflection ultrasonic switch is attached to a side wall in a room, (A) is a side view, (B) is a bottom view as seen from the arrow P of (A).

FIG. 2 shows a state in which a transmission wave detection sensor of a transmission type ultrasonic switch is attached to one side wall of a room, and a wave reception detection sensor is attached to the other side wall, (A) is a side view, and (B) is a side view. Is a bottom view from the arrow Q of (A)

3A and 3B show a state in which two transmission / reception detection sensors of a diffuse reflection type ultrasonic switch are attached back to back in the center of the room. (A) is a side view, (B) is a view from arrow R of (A). Bottom view

FIG. 4 shows a state in which two detection sensors dedicated to transmission of a transmission type ultrasonic switch are attached back to back in the center of the room, and the detection sensors dedicated to reception are attached to one side wall and the other side wall opposite to this. (A) is a side view,
(B) is a bottom view of the arrow S of (A)

5A and 5B are views for explaining the operation of the transmission / reception detection sensor of the diffuse reflection ultrasonic switch, FIG. 5A is a side view when normal, FIG. 5B is a side view when temperature rises, and FIG. ) Is a side view when a temperature gradient occurs

FIG. 6 is a curve diagram showing the relationship between the ultrasonic measurement distance and temperature.

FIG. 7 is a diagram for explaining the operation of the transmission-only detection sensor and the reception-only detection sensor of the transmission type ultrasonic switch,
(A) is a side view when the temperature is normal, (B) is a side view when the temperature rises, and (C) is a side view when a temperature gradient occurs.

FIG. 8 shows a state in which a conventional fire detection sensor is attached to a ceiling surface in a room, (A) is a side view, and (B) is (A).
Bottom view of T

[Explanation of symbols]

 1 Indoors 1A Ceiling surface 1B One side wall 1C Other side wall 3 Wave transmission / reception detection sensor 3A Wave transmission dedicated detection sensor 3B Wave reception dedicated detection sensor

Claims (6)

[Claims] 1. An ultrasonic transducer transmits an ultrasonic pulse, the ultrasonic pulse hits a detection body and is reflected, and the elapsed time until the ultrasonic transducer receives the ultrasonic pulse is measured. An ultrasonic fire detection device that uses an ultrasonic switch that detects the distance to the detection object and outputs a switch output that determines whether or not the detection object is within the distance range set from the outside. An ultrasonic fire detection device characterized by detecting a temperature change of air in an ultrasonic path according to a change in measured distance data to a placed detection object and issuing an abnormal alarm. 2. An ultrasonic transducer transmits an ultrasonic pulse, the ultrasonic pulse hits a detection body, is reflected, and the elapsed time until it is received by the ultrasonic transducer is measured. An ultrasonic fire detection device that uses an ultrasonic switch that detects the distance to the detection object and outputs a switch output that determines whether or not the detection object is within the distance range set from the outside. An ultrasonic fire detection device, which detects a deflection of an ultrasonic wave in a traveling direction due to a temperature gradient of air in an ultrasonic path based on a change in measured distance data to a placed detection object and issues an abnormal alarm. 3. An ultrasonic transducer transmits an ultrasonic pulse, the ultrasonic pulse hits a detection body and is reflected, and the elapsed time until the ultrasonic transducer receives the ultrasonic pulse is measured. An ultrasonic fire detection device that uses an ultrasonic switch that detects the distance to the detection object and outputs a switch output that determines whether or not the detection object is within the distance range set from the outside. By detecting the temperature change of the air in the ultrasonic path based on the change in the measured distance data to the placed detector, a primary warning is issued, and the deflection of the ultrasonic wave in the traveling direction due to the temperature gradient of the air is detected. An ultrasonic fire detector characterized by issuing a secondary alarm. 4. An ultrasonic transducer transmits an ultrasonic pulse, and an elapsed time until the ultrasonic pulse is received by a receiving unit arranged facing the ultrasonic transducer is measured,
An ultrasonic fire using an ultrasonic switch that detects the distance from the ultrasonic transducer to the receiving unit based on this measurement data and outputs a switch output to determine whether this distance is within a distance range set from the outside. An ultrasonic fire detecting device, characterized by detecting a temperature change of air in a path of an ultrasonic wave based on a change in measured distance data from the ultrasonic transducer to a receiving part and issuing an abnormal alarm. . 5. An ultrasonic transducer transmits an ultrasonic pulse, and the elapsed time until the ultrasonic pulse is received by a receiving unit arranged facing the ultrasonic transducer is measured,
An ultrasonic fire using an ultrasonic switch that detects the distance from the ultrasonic transducer to the receiving unit based on this measurement data and outputs a switch output to determine whether this distance is within a distance range set from the outside. A detection device, which detects a deflection of an ultrasonic wave in a traveling direction due to a temperature gradient of air in an ultrasonic path based on a change in measurement distance data from the ultrasonic transducer to a receiving unit and issues an abnormal alarm. Ultrasonic fire detector. 6. An ultrasonic transducer transmits an ultrasonic pulse, and an elapsed time until the ultrasonic pulse is received by a receiving unit arranged facing the ultrasonic transducer is measured,
An ultrasonic fire using an ultrasonic switch that detects the distance from the ultrasonic transducer to the receiving unit based on this measurement data and outputs a switch output to determine whether this distance is within a distance range set from the outside. A detection device, which detects a temperature change of the air in the ultrasonic path by a change in the measured distance data from the ultrasonic transducer to the receiving unit, and issues a primary alarm to detect the air in the ultrasonic path. An ultrasonic fire detection device, which detects a deflection in the traveling direction of ultrasonic waves due to a temperature gradient and issues a secondary alarm.