Abnormality detector and abnormality detection system

Abstract

To provide an abnormality sensor and an abnormality sensing system capable of sensing an abnormality even in an environment where a window is heavily soiled with accumulated dust or the like.SOLUTION: A flame sensor 1 is an abnormality sensor in which a sensor unit senses an abnormality within a sensing field through a recess 113 provided on a front surface of a sensor main body 11, which comprises: a nozzle portion 14 directed to the recess 113, and an air pipe 12 capable of supplying a high-pressure gas to the nozzle portion 14, and in which the high-pressure gas is blown to the recess 113 so as to remove deposited dust accumulated in the recess 113 or deposited dust adhering to the window 114 provided in the recess 113.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an abnormality detector having a sensing field of view through a recess in the main body, and more particularly to an abnormality detector and an abnormality detection system suitable for use in a dusty environment.

Background Art

[0002] Some abnormality detectors, such as flame detectors, have a sensing field of view through a window portion. In a flame detector, an infrared sensor is provided inside a window portion provided in a recess, and has a sensing field of view that spreads substantially conically from the infrared sensor through the window portion. When the window portion of such an abnormality detector becomes dirty, it becomes difficult to detect an abnormality. Therefore, the flame detector of Patent Document 1 has a function of detecting dirt on the window portion, and corrects the amount of received infrared light according to the detected amount of dirt to detect a flame.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the flame detector of Patent Document 1, when the dirt on the window portion becomes severe, it becomes impossible to receive infrared light, and it is difficult to detect a flame even with correction. For example, when using a flame detector in a place with a lot of dust, such as a biomass fuel warehouse, if dust accumulates on the window portion, infrared light cannot pass through. In such a state, it is difficult to perform flame detection even with correction. Such a situation is likely to occur not only in flame detectors but also in abnormality detectors having a sensing field of view through a window portion provided in a recess of the main body.

[0005] An object of the present invention is to provide an abnormality detector and an abnormality detection system capable of performing abnormality detection even in an environment where the window portion is severely contaminated with deposited dust or the like.

Means for Solving the Problem

[0006] An abnormality detector according to an embodiment of the present invention is an abnormality detector in which a sensor unit detects an abnormality within a detection visual field through a recess provided on the front surface of a detector main body, and includes a nozzle unit directed toward the recess and an air supply pipe capable of supplying high-pressure gas to the nozzle unit. The high-pressure gas is blown onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window provided in the recess. The nozzle unit is formed by arranging the tips of a plurality of air supply pipes in the width direction of the recess. Further, an abnormality detector according to an embodiment of the present invention is an abnormality detector in which a sensor unit detects an abnormality within a detection visual field through a recess provided on the front surface of a detector main body, and includes a nozzle unit directed toward the recess and an air supply pipe capable of supplying high-pressure gas to the nozzle unit. The high-pressure gas is blown onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window provided in the recess. The recess is formed long in a first direction, and the high-pressure gas is blown onto the recess in the first direction. Furthermore, an abnormality detection system according to an embodiment of the present invention includes an abnormality detector in which a sensor unit detects an abnormality within a detection visual field through a recess provided on the front surface of a detector main body, an air supply pipe, and a gas supply source. The abnormality detector has a nozzle unit directed toward the recess and an air supply pipe capable of supplying high-pressure gas to the nozzle unit. The air supply pipe of the abnormality detector is connected to the air supply pipe, and the high-pressure gas is blown onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window provided in the recess. The air supply pipe is extended to the vicinity of an opening of a warehouse storing a fire monitoring target and connected to a gas supply source that supplies the high-pressure gas. Also, an abnormality detector according to an embodiment of the present invention is an abnormality detector in which a sensor unit detects an abnormality within a detection visual field through a recess provided on the front surface of a detector main body, and includes a nozzle unit and an air supply pipe capable of supplying high-pressure gas to the nozzle unit. The air supply pipe bends in front of the detector main body to direct the nozzle unit toward the recess, and the high-pressure gas is blown onto the recess from the nozzle unit in front of the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window provided in the recess.

Effect of the Invention

[0007] The abnormality detector of the present invention can perform abnormality detection even in an environment where the window portion is severely contaminated with deposited dust or the like.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0009] As an example of an embodiment, an example in which a flame detector 1 is installed in a biomass warehouse 4 is shown. The flame detector 1 is a detector having a detection visual field V, and is an abnormality detector that detects an abnormal high temperature or fire within this detection visual field V by an infrared sensor which is a sensor unit. A plan view of the biomass warehouse 4 is shown in FIG. 1. In the biomass warehouse 4, wood pellets are stored as the biomass fuel 5. When a large amount of biomass fuel 5 such as wood pellets is stored, heat generated by oxidation or the like of the biomass fuel 5 accumulates inside and may cause spontaneous combustion. Therefore, it is managed so that heat does not accumulate inside the biomass fuel 5, but it is desirable to install a fire detector in case of spontaneous combustion. In the present embodiment, the flame detector 1 is installed with the biomass fuel 5 as the object to be monitored for fire.

[0010] In the biomass warehouse 4 of the embodiment shown in FIG. 1, a fire is detected by three flame sensors 1. FIG. 1 is a view looking down from above inside the biomass warehouse 4, which stores biomass fuel 5. The flame sensors 1 are installed near two corners of the biomass warehouse 4 and near the center of the opposing wall 41. The flame sensors 1 are directed towards the center of the biomass warehouse 4. Also, when viewed from the side, as shown in the cross-sectional view of the biomass warehouse 4 in FIG. 2, the flame sensors 1 are installed on the ceiling or a column near the ceiling, which is the upper part of the biomass warehouse 4, with the sensing field of view V directed obliquely downward. The three flame sensors 1 are connected to the receiver 22 via the sensing lines 21. In this way, the sensing equipment 2 including the sensing lines 21 and the receiver 22, and multiple flame sensors 1 monitor for fires throughout the biomass warehouse 4.

[0011] The flame sensor 1 senses the infrared rays emitted by a fire to detect a fire. Then, when the vicinity of the surface of the accumulated biomass fuel 5 becomes hot, the flame sensor 1 senses the infrared rays. The flame sensor 1 that has detected a fire by infrared rays emits a sensing signal. The sensing signal is sent to the receiver 22 via the sensing lines 21 shown in FIGS. 1 and 2. Then, a fire alarm is issued from the receiver 22 to a management center or the like provided in a separate building.

[0012] On one hand, the biomass warehouse 4 of the embodiment is provided with an air supply facility 3 for the flame detector 1. The air supply facility 3 has an air supply pipe 31 and a connection box 32. The air supply pipe 31 is connected to the flame detector 1. And the connection port 311 of the air supply pipe 31 is provided inside the connection box 32. The air supply pipe 31 extends to the vicinity of the opening 42 which is the entrance and exit of the biomass warehouse 4 that stores the biomass fuel 5, and is provided with the connection port 311. A compressor 33 which is a gas supply source of high-pressure gas can be connected to the connection port 311. Note that Fig. 2 shows a situation where the door 321 of the connection box 32 is open and the internal connection port 311 is exposed. Since a large amount of biomass fuel 5 is stored in the biomass warehouse 4, it is difficult for the administrator to go to the back side of the biomass warehouse 4, that is, the left side of Fig. 1 and the part facing the opening 42. For this reason, it is desirable to provide the receiver 22 and the connection box 32 which require the work and operation of the administrator in the vicinity of the opening 42 corresponding to the entrance and exit of the biomass warehouse 4.

[0013] The flame detector 1 is provided with a dirt detector (not shown). When detecting the dirt on the window portion 114, it transmits a dirt signal to the receiver 22 via the sensing line 21. Note that this dirt detector will be described later as a dirt detection function. When the receiver 22 reports dirt to a management center or the like, the administrator transports the compressor 33 which is a gas supply source to the vicinity of the connection box 32. Figs. 1 and 2 show the compressor 33 transported outside the opening 42. In the embodiment, the compressor 33 is transported from the outside of the biomass warehouse 4 when necessary. Then, the administrator connects the air supply tube (not shown) of the compressor 33 to the connection port 311 inside the connection box 32. When the compressor 33 is operated to send high-pressure gas from the compressor 33 to the air supply pipe 31, the high-pressure gas is sent to the flame detector 1 to remove the deposited dust 6. In the embodiment, an abnormal sensing system is formed by the flame detector 1, the sensing facility 2, and the air supply facility 3.

Example

[0014] Figure 3(a) shows a front view of the flame detector 1 of Example 1 facing obliquely downward. Figure 3(b) is a side view of the flame detector 1. The flame detector 1 has a detector body 11 and an air supply pipe 12. In the flame detector 1, the air supply pipe 12 is fixed on the detector body 11. A recess 113 recessed inward is formed in the center of the front surface 111 of the detector body 11, and the bottom surface of the recess 113 is a window portion 114. Inside the window portion 114, three infrared sensors (not shown) equipped with filters having different transmission wavelength bands are installed side by side vertically. And the window portion 114 is formed long in the vertical direction which is the first direction. The detection visual field V of the infrared sensor which is the sensor part spreads in a substantially conical shape toward the front of the detector body 11. And the recess 113 has a shape that spreads from the window portion 114 toward the front surface 111. The shape of this recess 113 is one of the factors determining the angle of the detection visual field V.

[0015] In the biomass warehouse 4, dust generated from the biomass fuel 5 is swirling. This dust adheres to the flame detector 1 and becomes deposited dust 6. The flame detector 1 is installed obliquely downward into the biomass warehouse 4, and the deposited dust 6 adheres to the front side of the window portion 114. In Figure 3, the deposited dust 6 adhering in the recess 113 is shown. As shown in Figure 3, the deposited dust 6 adheres thickly below the recess 113 and blocks the detection visual field V below the window portion 114. Also, deposited dust 6 (not shown) also adheres above the window portion 114 and becomes an obstacle to the detection visual field V.

[0016] The flame detector 1 of Example 1 has a dirt detection function for detecting dirt on the window portion 114. In the flame detector 1, a reflector (not shown) is provided on the side of the recess 113 facing the window portion 114 toward the window portion 114. And a light emitting portion and a light receiving portion (not shown) are provided inside the window portion 114, and the light receiving portion senses the reflection of the light from the light emitting portion by the reflector, thereby detecting the dirt on the window portion 114. When dust adheres to the window portion 114 and deposited dust 6 is generated, no reflected light enters the light receiving portion of the dirt detection function, and the flame detector 1 detects the dirt on the window portion 114. Then, the flame detector 1 transmits a dirt signal to the receiver 22 via the sensing line 21.

[0017] In the flame sensor 1 of the first embodiment, an air supply pipe 12 is fixed to the upper surface 112 of the sensor body 11. In the flame sensor 1 of the first embodiment shown in FIG. 3, two bent air supply pipes 12 are used. One end of each air supply pipe 12 is connected to a three-way branch 13, and the other end is connected to a nozzle portion 14. The air supply pipe 12 can supply high-pressure gas to the nozzle portion 14. In the first embodiment, the air supply pipe 12 and the nozzle portion 14 are integrally formed. The three-way branch 13 is also connected to the air supply pipe 31 of the air supply facility 3. The two air supply pipes 12 extend in a direction away from the three-way branch 13 near the upper surface 112 of the sensor body 11, then bend and approach each other, and further bend and extend side by side. The two juxtaposed air supply pipes 12 project from the upper surface 112 of the sensor body 11 toward the front surface 111, and then bend downward at the bending portion 121. Then, the two juxtaposed nozzle portions 14 are directed toward the recess 113.

[0018] The nozzle portion 14 is formed by arranging the tips of a plurality of branched air supply pipes 12 side by side in the width direction of the recess 113. In this way, by arranging two nozzle portions 14 and directing them toward the recess 113, high-pressure gas can be widely blown onto the recess 113. Then, the deposited dust 6 in the sensing visual field V is efficiently blown away by the high-pressure gas. The flame sensor 1 has a sensing visual field V that expands in a substantially conical shape, but the nozzle portion 14 and the air supply pipe 12 are located outside the sensing visual field V and do not interfere with the sensing visual field V.

[0019] In FIGS. 3 and 4, the nozzle portion 14 is formed by using the tips of two juxtaposed air supply pipes 12 as the nozzle portion 14, but the two tips may be combined with a cylindrical body having a large inner diameter, and the cylindrical body may be configured as the nozzle portion. It is desirable that the inner width of the nozzle portion is substantially equal to the outer width of the recess 113. This is because, with such an inner width, a predetermined high-pressure air can be applied to the entire deposited dust 6 accumulated in the recess 113, so that the deposited dust 6 can be surely blown away. The nozzle portion may have a shape in which the combined cylindrical body is crushed in the longitudinal direction and expanded in the width direction. On the other hand, depending on the way the high-pressure air is applied from the nozzle portion 14 to the recess 113, it is also possible to blow away the deposited dust 6 with a nozzle having a width narrower than the recess 113.

[0020] Incidentally, it is preferable to use a thin copper pipe with an outer diameter of about 5 mm for the air supply pipe 31. The reason why a copper pipe is preferable is that it is easy to process such as bending. Also, the reason why a thin pipe is preferable is that a small compressor 33 is used for the compressor 33 connected to the base end side. The biomass warehouse 4 is a relatively large warehouse. If the air supply pipe 31 is configured with a thick pipe, a large-capacity compressor 33 is required to send high-pressure air for blowing off the deposited dust 6. However, by making the air supply pipe 31 thinner and reducing the inner diameter, this problem can be solved.

Embodiment

[0021] FIG. 4 shows the flame sensor 7 of Embodiment 2 facing obliquely downward as seen from the front. The flame sensor 7 is also an abnormality sensor. Also in the flame sensor 7, an air supply pipe 72 is fixed to the upper surface 712 of the sensor body 71 in the same manner as in Embodiment 1. A recess 713 is formed in the front surface 711 of the sensor body 71, and the bottom surface of the recess 713 is a window portion 714. The sensor body 71 is the same as the sensor body 11 in the flame sensor 1 of Embodiment 1. FIG. 4 shows a situation where no deposited dust 6 is attached.

[0022] Unlike the flame sensor 1 of Embodiment 1, the flame sensor 7 of Embodiment 2 has one air supply pipe 72 and also one nozzle portion 73. The air supply pipe 72 protrudes from the upper surface 712 of the sensor body 71 toward the front surface 711, then bends downward at the bent portion 721, and directs the nozzle portion 73 toward the recess 713. Also in the flame sensor 7 of Embodiment 2, the deposited dust attached to the window portion 714 of the flame sensor 7 can be removed by blowing high-pressure gas. The bent portion 721 in the air supply pipe 72 is made of a material such as a flexible pipe, can be freely bent, and maintains the bent angle. Note that, similar to the flame sensor 1 of Embodiment 1, the nozzle portion 73 and the air supply pipe 72 in the flame sensor 7 of Embodiment 2 are also located outside the sensing visual field V and do not interfere with the sensing visual field V of an infrared sensor (not shown) which is a sensor portion. The tip of the air supply pipe 72 may have a shape that is flattened in the vertical direction and expanded in the width direction.

[0023] As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and design changes and the like within the scope not departing from the gist of the present invention are also included in the present invention. In addition, as long as there are no particular contradictions or problems in the purpose and configuration of the above-described embodiments, it is possible to combine them by diverting each other's technologies.

[0024] For example, the abnormality detector may be not only a flame detector but also other fire detectors or other abnormality detectors having a detection visual field V. Further, the abnormality detector is not limited to being installed obliquely downward as shown in FIG. 2. For example, the abnormality detector may be installed downward from the ceiling, or the abnormality detector may be installed laterally from the wall.

[0025] Also, even when the abnormality detector does not have a dirt detector, the deposited dust can be removed. In that case, the deposited dust can be removed periodically, or when inspecting, the administrator can check the state of the deposited dust and remove the deposited dust. Such operation can also be performed in an abnormality detector having a dirt detector.

[0026] In the embodiment, the compressor 33 is carried into the biomass warehouse 4 and used when necessary. However, a gas supply source of high-pressure gas such as the compressor 33 may be permanently installed in the biomass warehouse 4 and connected to the connection port 311. In that case, high-pressure gas may be automatically supplied to the air supply pipe 31 at regular intervals to remove deposited dust by blowing the high-pressure gas. Further, when the receiver 22 receives a dirt signal from the flame detector 1, the receiver 22 may directly or via a control panel (not shown) that controls the compressor 33 to start the compressor 33 and supply high-pressure air to the air supply pipe 31 of the flame detector 1. As a result, it is possible to provide a system that automatically removes dust accumulated in the recess 113 and the like of the flame detector 1 without the intervention of a person when dirt is detected. In this system, since the dust is removed only by injecting high-pressure air for several seconds, the compressor 33 may be started only for a certain period of time.

[0027] In the embodiment, the air supply pipes 31 connected to a plurality of abnormality sensors are combined into one to form a single connection port 311. However, the air supply pipes may each have a connection port without being combined. In that case, a strong high-pressure gas can be blown onto each individual abnormality sensor. Alternatively, a valve may be used to combine a plurality of air supply pipes into one connection port, and a strong high-pressure gas can be blown onto each individual abnormality sensor by switching the valve.

[0028] In Examples 1 and 2, the air supply pipes 12 and 17 and the nozzle portions 14 and 73 are integrally formed. However, the nozzle portions may be separate from the air supply pipes 12 and 17. Also, since it becomes difficult for dust to enter, the installation direction of the nozzle portion is preferably downward, but it is not limited to this. The air supply pipes may be installed with the nozzle portion facing upward, sideways, or obliquely, and a high-pressure gas for removing deposited dust may be blown.

[0029] In the embodiment of the present application, the flame sensor 1 is arranged as shown in FIG. 1. When the biomass warehouse 4 is large, the backs of two flame sensors 1 can be put together and installed so that each monitors both the left and right sides inside the biomass warehouse 4. When the flame sensors 1 are arranged and installed in this way, the air supply pipe 31 can be branched in the vicinity of the two flame sensors 1, making it easier to install the air supply pipe 31.

Description of Reference Numerals

[0030] 1 Flame sensor, 11 Sensor body, 111 Front surface, 112 Upper surface, 113 Recess, 114 Window portion, 12 Air supply pipe, 121 Bent portion, 13 Trifurcation, 14 Nozzle portion, 2 Sensing equipment, 21 Sensing wire, 22 Receiver, 3 Air supply equipment, 31 Air supply pipe, 311 Connection port, 32 Connection box, 321 Door, 33 Compressor, 4 Biomass warehouse, 41 Wall, 42 Opening, 5 Biomass fuel, 6 Deposited dust, 7 Flame sensor, 71 Sensor body, 711 Front side, 712 Upper side, 713 Recessed part, 714 Window part, 72 Air supply pipe, 721 Bent part, 73 Nozzle part V Sensing field of view

Claims

1. An abnormality detector that detects an abnormality within a sensing field of view through a recess provided on the front surface of a sensor body, comprising: a nozzle portion directed toward the recess; an air supply pipe capable of supplying high-pressure gas to the nozzle portion; and blowing the high-pressure gas onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window portion provided in the recess; the nozzle portion is formed by arranging the tips of a plurality of air supply pipes side by side in the width direction of the recess, characterized in that the abnormality detector is provided.

2. An abnormality detector that detects an abnormality within a sensing field of view through a recess provided on the front surface of a sensor body, comprising: a nozzle portion directed toward the recess; an air supply pipe capable of supplying high-pressure gas to the nozzle portion; and blowing the high-pressure gas onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window portion provided in the recess; the recess is formed long in a first direction; the abnormality detector is characterized in that the high-pressure gas is blown onto the recess in the first direction.

3. An abnormality detection system comprising: an abnormality detector that detects an abnormality within a sensing field of view through a recess provided on the front surface of a sensor body; an air supply pipe; and a gas supply source, the abnormality detector having a nozzle portion directed toward the recess and an air supply pipe capable of supplying high-pressure gas to the nozzle portion, connecting the air supply pipe to the air supply pipe, blowing the high-pressure gas onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window portion provided in the recess; the air supply pipe is extended to the vicinity of an opening of a warehouse storing a fire monitoring target and connected to a gas supply source that supplies the high-pressure gas, characterized in that the abnormality detection system is provided.

4. An abnormality detector that detects an abnormality within a sensing field of view through a recess provided on the front surface of a sensor body, comprising: a nozzle portion; an air supply pipe capable of supplying high-pressure gas to the nozzle portion; and the air supply pipe is bent in front of the sensor body to direct the nozzle portion toward the recess; the high-pressure gas is blown from the nozzle portion in front of the recess onto the recess to remove deposited dust accumulated in the recess or deposited dust adhering to a window portion provided in the recess, characterized in that the abnormality detector is provided.

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