JP7795887B2 - Charged water particle spraying system - Google Patents

Description

The present invention relates to a charged water particle spraying system that sprays charged water particles from the tip of the ladder of a ladder fire truck to a target area such as a building where a fire has broken out to extinguish the fire.

Conventionally, a charged water particle spraying system has been known that sprays electrically charged water particles onto a target area of a building or other building where a fire has broken out to extinguish the fire. This system is expected to be able to efficiently extinguish fires with a small amount of water and reduce water damage.

JP 2009-106405 A Japanese Patent Application Laid-Open No. 2018-183712

In conventional charged water particle spray systems, charged water particles are sprayed from a charged spray head onto a target area where a fire is occurring, suppressing and extinguishing the fire while also eliminating smoke that has arisen in the target area. For example, when negatively charged water particles are sprayed from a charged spray head, if the particulate mixture containing smoke particles and the like that arises in the target area is positively charged, it is believed that the particulates (smoke particles) contained in the particulate mixture will be attracted to and captured by the charged water particles due to electrostatic force, thereby more effectively eliminating smoke. Also, when positively charged water particles are sprayed from a charged spray head, if the particulate mixture is negatively charged, it is believed that the particulates (smoke particles) contained in the particulate mixture will be attracted to and captured by the charged water particles due to electrostatic force, thereby more effectively eliminating smoke.

However, whether the particulate gas mixture generated in the target area is negatively or positively charged varies depending on the type of combustible material and the characteristics of the fire, and sufficient smoke suppression performance may not be achieved unless the particulate gas mixture is charged with the opposite polarity to the charged water particles.

The objective of the present invention is to provide a charged water particle spraying system that sprays charged water particles under optimal spraying conditions according to the type of smoke or fire, ensuring high fire and smoke extinguishing performance.

(Charged water particle spraying system)
The present invention provides a system for dispensing electrically charged water particles, comprising:
The method is characterized by identifying the type of smoke or fire and spraying charged water particles to a target area under spray conditions that correspond to the results of the identification.

(Dispersion conditions according to type of smoke)
The type of smoke is identified as either cellulose-based smoke or hydrocarbon-based smoke, and charged water particles are dispersed under dispersion conditions according to the result of the discrimination of cellulose-based smoke or hydrocarbon-based smoke.

(Charge polarity of charged water particles depending on type of smoke)
If the identification result is cellulose-based smoke, the charged water particles are negatively charged and dispersed, and if the identification result is hydrocarbon-based smoke, the charged water particles are positively or negatively charged and dispersed.

(Dispersion conditions according to the type of fire)
The type of fire is identified as either a wood fire or an oil fire, and charged water particles are sprayed under spray conditions according to the results of the identification of the wood fire or oil fire.

(Charge polarity of charged water particles depending on the type of fire)
If the identification result is a wood fire, the charged water particles are negatively charged and sprayed, and if the identification result is an oil fire, the charged water particles are either positively or negatively charged and sprayed.

(Control of the amount of charge or charge of charged water particles)
The amount of charge or the amount of charge of the charged water particles to be dispersed is controlled depending on the type of smoke or the type of fire.

(Effect of the charged water particle spraying system)
According to the charged water particle spraying system of the present invention, when charged water particles are sprayed onto a target area in the event of a fire in a building such as a building, the type of smoke or the type of fire is identified, and the charged water particles are sprayed onto the target area under spray conditions according to the identification results.This means that the operator does not need to identify the type of smoke or the type of fire and set the spray conditions, and the charged water particles can be automatically sprayed under optimal spray conditions according to the type of smoke or fire, making it possible to achieve high fire and smoke extinguishing performance.

(Effect of spray conditions depending on the type of smoke)
The smoke type is identified as either cellulose-based or hydrocarbon-based, and charged water particles are sprayed under spray conditions corresponding to the identification result of either cellulose-based or hydrocarbon-based smoke. The inventors of the present application have found that, for cellulose-based smoke, higher smoke elimination performance is achieved when the charged water particles are sprayed with a negative charge polarity than when the charged water particles are sprayed with a positive charge polarity, while, for hydrocarbon-based smoke, there is no difference in smoke elimination performance whether the charged water particles are sprayed with a positive charge polarity or a negative charge polarity. Therefore, when cellulose-based smoke is identified, the charged water particles are sprayed with a negative charge polarity, and when hydrocarbon-based smoke is identified, the charged water particles are sprayed with a positive charge or a negative charge polarity, thereby making it possible to obtain high smoke elimination performance.

(Effects of spraying conditions depending on the type of fire)
In addition, the type of fire is identified as either a wood fire or an oil fire, and charged water particles are sprayed under spray conditions according to the identification result of the wood fire or oil fire.Since a wood fire is a fire caused by the combustion of cellulose-based materials, and an oil fire is a fire caused by the combustion of hydrocarbon-based materials, if a wood fire is identified, the charged water particles are sprayed with a negative polarity, just as when cellulose-based smoke is identified, and if an oil fire is identified, the charged water particles are sprayed with a positive or negative polarity, just as when hydrocarbon-based smoke is identified, making it possible to achieve high smoke extinguishing performance.

(Effect of controlling the amount of charge or charge of charged water particles)
In addition, by controlling the amount of charge or the amount of charge of the charged water particles to be sprayed depending on the type of smoke or the type of fire, it is possible to achieve higher fire and smoke extinguishing performance.

1 is an explanatory diagram showing an embodiment of a charged water particle spraying system of the present invention. 2 is an explanatory diagram showing an embodiment of the charged water particle emitting portion of FIG. 1. 3 is an explanatory diagram showing an embodiment of a charged spray head provided in the charged water particle discharge unit of FIG. 2. 2 is an explanatory diagram showing an embodiment of the high-voltage power supply unit of FIG. 1 together with an electrostatic spray head. FIG. 2 is an explanatory diagram showing an embodiment of the fire extinguishing agent supply unit of FIG. 1 together with an electrostatic spray head. FIG. FIG. 2 is an explanatory diagram showing the suction device of FIG. 1. 2 is an explanatory diagram illustrating an embodiment of the smoke detector of FIG. 1; FIG. FIG. 1 is an explanatory diagram showing a system block diagram of a smoke detector. FIG. 1 is an explanatory diagram showing a firefighting activity using a ladder fire engine equipped with the charged water particle spraying system of the present invention. 1 is a flowchart showing the control operation of the charged water particle spraying system of the present invention.

Below, an embodiment of the charged water particle spraying system according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiment.

[Basic Concept of the Embodiment]
First, the basic concept of the embodiment will be described. The embodiment generally relates to a charged water particle spraying system that sprays charged water particles to a target area, and is installed on a mobile object such as a fire engine, for example.

Here, the "charged water particle spraying system" identifies the type of smoke or fire and sprays charged water particles into a target area under spraying conditions according to the results of that identification, and includes the concepts of charged water particle spraying equipment and charged water particle spraying devices used to construct a charged water particle spraying system. Furthermore, the "target area" is a concept that includes sources of smoke, etc., fire sources, or the locations or spaces where these exist, as well as the area where smoke, etc., diffuses.

Furthermore, "charged water particles" are water particles contained in a fire extinguishing agent that have been electrically charged, for example, water particles that have been charged using an induction charging method in which the water particles pass through a high electric field generated by a predetermined high voltage applied from a high-voltage power supply.

Furthermore, "spraying charged water particles onto a target area" means that any method of spraying can be used as long as the charged water particles can be moved to the target area and sprayed there. For example, an airflow can be generated toward the target area, and a charged water particle airflow containing charged water particles can be released into the airflow, thereby moving the charged water particles to the target area and spraying them there.

The "charged water particle spray system" also identifies the type of smoke as either cellulose-based or hydrocarbon smoke, and sprays charged water particles under spray conditions that correspond to the results of the identification of cellulose-based or hydrocarbon smoke.

Here, "cellulose-based smoke" includes the relatively white or gray smoke (white smoke or gray smoke) that is produced when cellulose-containing wood or paper is smoked, and "hydrocarbon-based smoke" includes the relatively black smoke (black smoke) that is produced when hydrocarbon-containing liquid fuels, oils and fats, synthetic resins, etc. are burned. Note that water vapor is not included in white smoke, so "cellulose-based smoke" does not include water vapor.

The "charged water particle spraying system" sprays negatively charged water particles when cellulose-based smoke is identified, and sprays either positively or negatively charged water particles when hydrocarbon-based smoke is identified.

The "charged water particle spraying system" also identifies the type of fire as either a wood fire or an oil fire, and sprays charged water particles under spraying conditions that correspond to the results of the fire identification.

Here, a "wood fire" refers to a fire that produces cellulose-based smoke, which is relatively white to gray (white smoke or gray smoke), when cellulose-containing wood or paper smokes, and is referred to as a "wood fire" for convenience. Furthermore, a "oil fire" refers to a fire that produces hydrocarbon-based smoke, which is relatively black (black smoke), when hydrocarbon-containing liquid fuels, oils, synthetic resins, etc. burn, and is referred to as an "oil fire" for convenience.

The "charged water particle spraying system" sprays negatively charged water particles when a wood fire is identified, and sprays either positively or negatively charged water particles when an oil fire is identified.

Furthermore, the charged water particle spraying system controls the amount of sprayed or the amount of charge of the charged water particles depending on the type of smoke or type of fire.

In addition, the charged water particle spraying system, as an example, includes multiple charged spray heads, a smoke detector, and a control unit, and specific embodiments will be described using this configuration.

Here, an "electrically charged spray head" is a device that sprays electrically charged water particles to distribute them over a target area, and in this embodiment, multiple electrically charged spray heads are provided. Furthermore, spraying electrically charged water particles from an electrically charged spray head may also be considered as dispersing electrically charged water particles over a target area.

Furthermore, a "smoke detector" identifies the type of smoke or fire based on the particulate mixture containing smoke particles generated in the target area. Here, a "particulate mixture" is a gas containing particulates, including smoke particles and monodisperse particles generated by fire, as well as combustion product gases such as carbon dioxide and carbon monoxide.

Furthermore, the "control unit" controls the conditions for spraying charged water particles depending on the type of smoke or fire identified by the smoke detector, and the details of controlling the spray conditions are as described above.

Specific embodiments are described below. In the specific embodiments described below, the "target spray area" is a "fire compartment of a building" and "multiple electrically charged spray heads and smoke detectors" are installed at the end of the ladder of a ladder fire truck.

[Specific Contents of the Embodiment]
The specific contents of the embodiment will be described separately as follows.
a. Overview of the charged water particle spraying system b. Charged water particle emission section b1. Air blower section b2. Charged water particle generation section b3. Charged spray head b4. Emission direction adjustment section c. High-voltage power supply section c1. Circuit configuration of the charged water particle generation section c2. High-voltage variable circuit c3. Polarity reversal circuit c4. High voltage application c5. Abnormal current detection circuit d. Fire extinguishing agent supply section e. Charged water particle charge polarity switching control f. Suction device f1. Sampling pipe f2. Tube f3. Suction pump g. Holding device h. Smoke detector h1. Smoke detection section h2. Detection circuit section h3. Signal detection section h4. Recognition section i. Smoke type and charged water particle charge polarity i1. Charge polarity of water particles for cellulose-based smoke i2. Charge polarity of water particles for hydrocarbon-based smoke i3. Initial setting of charged water particle charge polarity j. k. Control panel k. Ladder fire engine equipped with the charged water particle spraying system l. Control operation of the charged water particle spraying system m. Modification of the present invention n. Supplementary notes

[a. Overview of the charged water particle spraying system]
The charged water particle spraying system of this embodiment is mounted on a fire truck such as a ladder fire engine and sprays charged water particles toward a target area. Its configuration and structure are arbitrary, but for example, as shown in Figure 1, it includes a charged water particle discharge unit 10, an operation panel 14, a fire extinguishing agent supply unit 16, a high-voltage power supply unit 18, a smoke detector 80, and a suction device 82, and the operation panel 14 is provided with an operation display unit 20 and a control unit 21.

The charged water particle discharge unit 10 includes an air blower 28 and a charged water particle generator 30, and is mounted on a stand 40 so that it can rotate freely in the vertical and horizontal directions. A water supply pipe 22 from the extinguishing agent supply unit 16, a high-voltage cable 24 from the high-voltage power supply unit 18, and signal cables 26e and 26f are connected to the discharge pipe 22, as well as signal cables 26a and 26d from the control unit 21 of the operation panel 14. Here, signal cable 26a is connected to the discharge direction adjustment unit of the air blower 28, and signal cables 26d, 26e, and 26f are connected to the on-off valves, switch circuits, and current detection resistors provided for each of the multiple charged spray heads arranged in the charged water particle generator 30.

The smoke detector 80 is installed on the side of the charged water particle emitter 10 and identifies the type of smoke or fire from the smoke particles contained in the particulate mixture sucked in by the suction device 82. A signal cable 26c is connected to the control unit 21 of the operation panel 14.

The suction device 82 is provided on the side of the charged water particle discharger 10 and sucks in a particulate mixture containing smoke particles from a fire that has occurred from the fire compartment side of the building toward the smoke detector 80. A signal cable 26b from the control unit 21 of the operation panel 14 is also connected to the suction pump 88. The specific configuration and structure of the suction device 82, including an explanation of the components assigned reference numerals in Figure 1, will be described later.

In the description of Figure 1, the X-Y-Z directions are mutually orthogonal directions. Specifically, when looking at the front of the charged water particle generator 30 placed on the stand 40 in a non-rotating state, the X direction is the left-right direction (not shown in Figure 1), the Y direction is the up-down direction, and the Z direction is the front-to-back direction. Furthermore, the +X side of the X direction is the right side and the -X side is the left side; the +Y side of the Y direction is the top side and the -Y side is the bottom side; and the +Z side of the Z direction is the front side and the -Z side is the back side. This also applies to Figures 2 and 6, which illustrate embodiments of the present invention.

[b. Charged water particle emission unit]
The following provides a more detailed description of the charged water particle emitting unit 10. The charged water particle emitting unit 10 emits a charged water particle airflow 12 containing charged water particles, thereby dispersing the charged water particles toward a fire compartment of a building that includes a target for fire extinguishing or fire prevention. The configuration and structure of the unit are arbitrary, but it may include, for example, an air blower 28 and a charged water particle generator 30.

The blower unit 28 generates an airflow toward the fire compartment. Charged water particles are sprayed into the airflow from the blower unit 28 using multiple charged spray heads attached to the charged water particle generator 30, which is located at the outlet of the blower unit 28. The charged water particle airflow 12 containing the charged water particles is then released toward the fire compartment. The charged water particle release unit 10 is installed, for example, at the tip of the ladder of a ladder fire truck, and releases the charged water particle airflow 12 from the outside of a building or other structure where a fire has occurred through an exterior wall opening such as a window toward the fire compartment to extinguish the fire.

Figure 2 shows the charged water particle emission unit 10 of Figure 1 in more detail, with Figure 2(A) showing a rear view from the rear, Figure 2(B) showing a side view from the left, and Figure 2(C) showing a front view from the front.

(b1. Air blower)
The blower 28 will now be described in more detail. The blower 28 has a cavity with openings at the front and rear, and an axial fan 34 driven by a fan motor 36 is disposed therein. The rotation of the axial fan 34 pressurizes air drawn in through the rear opening and releases the airflow from the front opening. The volume of the airflow released from the blower 28 is arbitrary, but for example, a maximum volume of approximately 400 ^m3 /min is used. The volume of air can be changed as needed by changing the rotation speed of the axial fan 34 using the fan motor 36.

When the charged water particle discharge unit 10 is installed at the end of the ladder of a ladder fire truck, it is possible to place the charged water particle discharge unit 10 within several meters of the fire compartment of the building, so the airflow volume of the blower unit 28 is set so that the reach of the charged water particle airflow 12 to the fire compartment is, for example, approximately 10 meters. In addition, a protective cover 38 made of multiple rings, wire mesh, etc. is attached to the rear opening of the blower unit 28.

(b2. Charged water particle generating unit)
The charged water particle generator 30 will be described in more detail. The charged water particle generator 30 is disposed on the front opening side of the air blower 28. When viewed from the front of the charged water particle emitter 10 as shown in FIG. 2(C), the charged water particle generator 30 has, for example, ten charged spray heads 32 arranged in a ring shape inside a support ring 31. Here, the spray axis of each charged spray head 32 is disposed so as to intersect with the emission axis 25 of the charged water particle airflow 12, and when viewed from the left side of the charged water particle emitter 10 as shown in FIG. 2(B), the spray axis of each charged spray head 32 is disposed so as to intersect with the emission axis 25 at point P forward.

The intersection angle θ between the spray axis of the charged spray head 32 and the discharge axis 25 of the charged water particle airflow 12, which intersect at point P, is a predetermined angle that ensures the sprayed charged water particles are well contained in the airflow, taking into account the spray speed and spread angle of the charged water particles from the charged spray head 32, the wind speed of the airflow from the blower section 28, etc., and is, for example, a predetermined angle in the range of 45° to 90°, such as 60°.

(b3. Charging spray head)
Next, the charged spray head 32 provided in the charged water particle generator 30 in Fig. 2 will be described in more detail. Fig. 3 shows the charged spray head 32, with Fig. 3(A) showing a perspective view from the spray side and Fig. 3(B) showing a cross-sectional view from the side.

As shown in Figure 3, the electrically charged spray head 32 sprays and contains electrically charged water particles into the airflow from the air blower 28. Its configuration and structure are arbitrary, but as an example, it is composed of a body 54, a spray nozzle 56, an electrode holder 58, an induction electrode 60, a water-side electrode 62, and a water supply connection 64. The body 54, spray nozzle 56, electrode holder 58, and water supply connection 64 are made of insulating materials.

A through hole is formed inside the body 54 in the direction of the spray axis 55, and the conductive water-side electrode 62 is fitted from the spray side, with the water supply connection 64 fitted above it. An earth cable is connected from the outside to the electrode connection 62a of the water-side electrode 62. Pressurized fire-fighting water, for example, is supplied to the water supply connection 64 as a fire extinguishing agent. A spray nozzle 56 is provided on the spray side of the water-side electrode 62, and sprays water droplets with an average particle diameter of, for example, 100 to 300 μm.

A ring-shaped induction electrode unit 60 is positioned by an electrode holder 58 in the open space on the spray side of the spray nozzle unit 56. The induction electrode unit 60 may have any configuration or structure, but may, for example, be formed by insulating a conductive electrode core material. An external voltage application cable is connected to the cable connection unit 60a of the induction electrode unit 60.

A predetermined voltage (e.g., 10 kV DC voltage) adjusted within a predetermined adjustment range (e.g., 0.5 kV to 20 kV) within the voltage range capable of charging water particles is applied between the induction electrode unit 60 and the water-side electrode unit 62 from the high-voltage power supply unit 18 shown in Figure 1. This applied voltage creates a predetermined external electric field around the ring portion of the induction electrode unit 60, and water particles sprayed from the spray nozzle unit 56 are charged by the induction charging method as they pass through the ring portion of the induction electrode unit 60.

Here, the specified adjustment range (i.e., the specified adjustable range) may include a voltage range in which water particles cannot be charged, as long as it can be adjusted to a specified voltage that can charge water particles. The polarity (positive/negative) of the applied voltage is switched by the high-voltage power supply unit 18.

When a predetermined DC voltage is applied to the induction electrode unit 60 so that the potential of the water-side electrode unit 62 is positive relative to the reference potential (earth potential, 0 V) of the water-side electrode unit 62, the water particles sprayed from the spray nozzle unit 56 are negatively charged. When a predetermined DC voltage is applied to the induction electrode unit 60 so that the potential of the water-side electrode unit 62 is negative relative to the reference potential (earth potential, 0 V), the water particles sprayed from the spray nozzle unit 56 are positively charged. Furthermore, when the absolute value of the voltage applied between the induction electrode unit 60 and the water-side electrode unit 62 is set within the range of, for example, 0.5 kV to 20 kV, spark discharge is prevented, and a spray of charged water particles is generated while ensuring safety.

The configuration and structure of the charged spray head 32 are arbitrary and are not limited to those shown in Figure 3. Any suitable or known structure that can generate water particles and charge the generated water particles to spray charged water particles can be used.

(b4. Release direction adjustment section)
The following provides a more detailed description of the emission direction adjustment unit provided in the charged water particle emission unit 10. The emission direction adjustment unit adjusts the emission direction of the charged water particle airflow 12 from the charged water particle emission unit 10, and while the configuration and structure thereof are arbitrary, as an example, a left-right direction adjustment unit 44 and a up-down direction adjustment unit 48 are provided as shown in FIG.

The blower section 28 of the charged water particle emitter 10 is supported on the base 40 by a pivot support section 42 so that it can rotate left and right around a left-right pivot shaft 46, and also so that it can rotate up and down around a vertical pivot shaft 50. A left-right direction adjustment section 44 is also located below the base 40. The left-right direction adjustment section 44 is, for example, motor-driven, and by supporting the pivot support section 42 so that the left-right pivot shaft 46 is positioned on the drive shaft, the charged water particle emitter 10 can be rotated left and right around the left-right pivot shaft 46, thereby adjusting the left and right emission direction of the charged water particle airflow 12.

In addition, a vertical direction adjustment unit 48 is disposed on the right side of the rotation support unit 42, where the vertical rotation shaft 50 is located. The vertical direction adjustment unit 48 is, for example, motor-driven, and by supporting the rotation support unit 42 so that the vertical rotation shaft 50 is located on the drive shaft, the charged water particle discharge unit 10 can be rotated vertically around the vertical rotation shaft 50 as the rotation axis, thereby adjusting the vertical discharge direction of the charged water particle airflow 12.

Here, the left-right pivot shaft 46 and the up-down pivot shaft 50 are adjusted to be at predetermined positions forward (on the release side) of the center of gravity 52 of the charged water particle discharger 10. This stabilizes the release direction of the charged water particle airflow 12 discharged by the charged water particle discharger 10 even when subjected to a recoil, allowing the operator to easily adjust the release direction to the desired direction. Furthermore, if the charged water particle discharger 10 is installed in a basket section attached to the end of the ladder of a ladder fire truck, the release direction of the charged water particle airflow 12 from the charged water particle discharger 10 is highly stable even when the basket section is tilted, preventing the discharge direction of the charged water particle airflow 12 from being directed in an unexpected direction and ensuring safe operation.

[c. High voltage power supply section]
The high-voltage power supply unit 18 will be described in more detail. The high-voltage power supply unit 18 supplies a high voltage for generating charged water particles to the charged-water particle emitting unit 10 via a high-voltage cable 24. The configuration and function of the high-voltage power supply unit 18 are arbitrary, but for example, as shown in Fig. 4, it may include a high-voltage variable circuit 66 that adjusts the supplied voltage, a polarity reversal circuit 68 that switches the polarity of the supplied voltage, an abnormal current detection circuit 74 that detects abnormal current flowing between the induction electrode unit 60 and the water-side electrode unit 62 of the charged spray head 32, and a selection circuit 72 that switches between applying and stopping voltage application to the charged spray head 32. In Fig. 4, the cable connected to the induction electrode unit 60 side of the high-voltage cable 24 is referred to as a voltage application cable 24a, and the cable connected to the water-side electrode unit 62 side is referred to as an earth cable 24b.

(c1. Circuit configuration of charged water particle generator)
The circuit configuration of the charged water particle generator 30, which is connected to the high-voltage power supply 18 via the high-voltage cable 24, will be described in more detail below. Figure 4 shows the circuit configuration of the charged water particle generator 30, which includes the high-voltage power supply 18 and multiple charged spray heads 32. Each charged spray head 32 includes an induction electrode 60 and a water-side electrode 62. A voltage application cable 24a from the high-voltage power supply 18 branches off for each charged spray head 32 and is connected to the induction electrode 60 of each charged spray head 32 via a switch circuit 75 and a current-limiting resistor 76. The water-side electrode 62 of each charged spray head 32 is also commonly connected via a current-detecting resistor 78, to which an earth cable 24b from the high-voltage power supply 18 is connected via a switch 77 circuit.

Normally, switch circuits 75 and 77 are on, and high-voltage power supply 18 applies a high voltage between induction electrode 60 and water-side electrode 62, charging the water particles sprayed from charged spray head 32. Highly insulated, high-voltage cables are used for voltage application cable 24a and earth cable 24b, but when applying DC voltage, the positive cable should be a high-voltage cable and the negative cable can be a regular low-voltage cable.

(c2. High voltage variable circuit)
The high-voltage variable circuit 66 will now be described in more detail. The high-voltage variable circuit 66 adjusts the voltage applied between the induction electrode unit 60 and the water-side electrode unit 62 in response to a control signal from the control unit 21 of the operation panel 14, thereby enabling the charged water particle airflow containing charged water particles with a charge appropriate for fire extinguishing and smoke suppression to be emitted from the charged spray head 32 into the fire compartment. Furthermore, by lowering the absolute value of the applied voltage, the charged water particles have a reduced charge, which makes it possible to prevent discharge accidents that may occur due to an increase in the charge of the charged water particles on a fire extinguishing or fire prevention target that is easily charged.

(c3. Polarity reversal circuit)
The polarity reversing circuit 68 will be described in more detail. The polarity reversing circuit 68 switches the polarity of the voltage applied between the induction electrode unit 60 and the water-side electrode unit 62 in response to a control signal from the control unit 21 of the operation panel 14. This switches the polarity of the charged water particles sprayed from the charged spray head 32 between positive and negative polarities, allowing a charged water particle airflow containing charged water particles of a polarity suitable for fire and smoke extinguishing to be emitted into the fire compartment. For example, by emitting a charged water particle airflow containing charged water particles charged with a polarity opposite to the polarity of the particulate air-fuel mixture generated in the fire compartment, better fire and smoke extinguishing performance can be expected.

(c4. Application of high voltage)
The case where a high voltage is applied between the induction electrode section 60 and the water-side electrode section 62 of the charged spray head 32 from the high-voltage power supply section 18 will be described in more detail below, taking as an example the case where a DC voltage is applied.

The high-voltage variable circuit 66 adjusts the voltage output from the high-voltage variable circuit 66 to a predetermined DC voltage in response to a control signal from the control unit 21 of the operation panel 14. "Adjusting to a predetermined DC voltage" here means adjusting to a DC voltage capable of charging water particles, for example, adjusting to a DC voltage selected from the range of 0.5 kV to 20 kV (+0.5 kV to +20 kV or -0.5 kV to -20 kV), which is the voltage range capable of charging water particles.

The polarity reversing circuit 68 determines whether to switch the polarity of the specified DC voltage adjusted and output by the high-voltage variable circuit 66 in response to a control signal from the control unit 21 of the operation panel 14, and adjusts the polarity of the DC voltage applied between the induction electrode unit 60 and the water side electrode unit 62.

For example, if the high-voltage variable circuit 66 adjusts the specified DC voltage to +10 kV DC (positive DC), and the polarity is not switched by the polarity reversal circuit 68, the potential of the induction electrode unit 60 will be +10 kV, with the water-side electrode unit 62 at the reference potential (earth potential, 0 V), and a +10 kV DC voltage (positive DC voltage) will be applied between the induction electrode unit 60 and the water-side electrode unit 62, increasing the potential of the induction electrode unit 60 relative to the potential of the water-side electrode unit 62. As a result, the water particles sprayed from the charged spray head 32 will be negatively charged.

On the other hand, when the high-voltage variable circuit 66 adjusts the specified DC voltage to +10 kV DC (positive DC), and the polarity is switched by the polarity reversal circuit 68, the potential of the induction electrode unit 60 becomes -10 kV with the water-side electrode unit 62 as the reference potential (earth potential, 0 V), and a DC voltage of -10 kV (negative DC voltage) is applied between the induction electrode unit 60 and the water-side electrode unit 62, making the potential of the induction electrode unit 60 lower than the potential of the water-side electrode unit 62. As a result, the water particles sprayed from the charged spray head 32 are positively charged.

(c5. Abnormal current detection circuit)
The abnormal current detection circuit 74, which functions as an abnormal current detector, will now be described in more detail. The abnormal current detection circuit 74 detects abnormal currents flowing due to an insulation abnormality between the induction electrode 60 and the water-side electrode 62 for each of the multiple charged spray heads 32. Here, an insulation abnormality refers to an abnormality in electrical insulation, and is a concept that includes insulation degradation, insulation failure, insulation breakdown, short circuit, etc.

A series circuit consisting of a current limiting resistor 76, induction electrode 60, water-side electrode 62, and current detection resistor 78 is provided on the branch line of the voltage application cable 24a, which branches off for each charged spray head 32. The signal cable 26f from the abnormal current detection circuit 74 is connected to the water-side electrode 62 side of each current detection resistor 78 via separate signal lines, and the earth cable 24b is connected to the abnormal current detection circuit 74, so that the voltage across each current detection resistor 78 is input to the abnormal current detection circuit 74 as a current detection voltage signal.

The resistance value of the current limiting resistor 76 is set to a predetermined value, for example, in the range of 1 to 10 MΩ, and the resistance value of the current detection resistor 78 is set to any value that is sufficiently lower than the resistance value of the current limiting resistor 76, for example, a predetermined resistance value in the range of 1 to 10 kΩ. Specifically, the resistance value of the current detection resistor 78 is set so that the voltage across the current detection resistor 78 due to an abnormal current flowing due to an insulation abnormality in the charged spray head 32 is below a predetermined low voltage, for example, 10 V or less. In other words, the current flowing through the current detection resistor 78 reaches its maximum when a short circuit occurs between the induction electrode portion 60 and the water side electrode portion 62 of the charged spray head 32, and the voltage across the current detection resistor 78 also reaches its maximum voltage. Therefore, the resistance value of the current detection resistor 78 is set so that this maximum voltage is below, for example, 10 V.

Furthermore, because the signal cable 26f of the abnormal current detection circuit 74 is connected to the water-side electrode portion 62 of each current detection resistor 78 via a separate signal line, it can detect abnormal currents caused by poor insulation for each charged spray head 32. In this embodiment, ten charged spray heads 32 are provided (see Figure 2), and the abnormal current detection circuit 74 outputs one of abnormal current detection signals E1-E10 to the control unit 21 corresponding to the charged spray head 32 in which an abnormal current was detected. The configuration and function of the comparator are arbitrary, but for example, a number of comparators corresponding to the number of charged spray heads 32 are provided. For example, the comparator receives a current detection voltage signal, which is the voltage across the current detection resistor 78 provided on the corresponding charged spray head 32 side. When the current detection voltage signal is equal to or exceeds a predetermined threshold voltage, the comparator detects an abnormal current and outputs an abnormal current detection signal, rising from L level to H level.

The type and configuration of the comparator that operates in this manner are arbitrary, but a Schmitt trigger circuit is used, for example. The Schmitt trigger circuit outputs an abnormal current detection signal by causing its output to rise from L level to H level when the current detection voltage signal exceeds a first threshold voltage. Then, when the current detection voltage signal falls below a second threshold voltage that is lower than the first threshold voltage, its output falls from H level to L level, thereby stopping the output of the abnormal current detection signal. This hysteresis characteristic allows for the output of a stable abnormal current detection signal in response to fluctuations in the current detection voltage signal.

In this way, the current detection resistor 78 and abnormal current detection circuit 74 are located on the reference potential side, the resistance value of the current detection resistor 78 is sufficiently low compared to the resistance value of the current limiting resistor 76, and the circuit is configured to reduce the voltage across the current detection resistor 78 due to an abnormal current flowing due to an insulation abnormality in the charged spray head 32. This eliminates the need for special high-voltage circuit components for the abnormal current detection circuit 74, and because high voltage is not applied to the abnormal current detection circuit 74, there is no need for an insulation structure that can withstand high voltages. This allows for a simple insulation structure, and makes it possible to simply and easily detect a charged spray head 32 with an insulation abnormality from among multiple charged spray heads 32, without compromising safety.

The control unit 21 receives abnormal current detection signals E1-E10 from the abnormal current detection circuit 74. When one of these signals E1-E10 is received, the control unit 21 determines whether an abnormal current has been detected in the charged spray head 32 corresponding to the received abnormal current detection signal, and performs control to stop the application of high voltage to the charged spray head 32 in which the abnormal current was detected. To perform this stop control, a selection circuit 72 is provided in the high-voltage power supply unit 18, and a switch circuit 75 is provided in each branch line of the voltage application cable 24a. Furthermore, the selection circuit 72 receives control signals from the control unit 21 that turn the switch circuit on and off, and the signal cable 26e from the selection circuit 72 is connected to each switch circuit 75 via a separate signal line.

In response to a control signal from the control unit 21, the selection circuit 72 outputs an OFF activation signal to the switch circuit 75 corresponding to the charged spray head 32 in which an abnormal current has been detected, turning it off, thereby stopping the application of high voltage to the charged spray head 32 in which an abnormal current has been detected and ensuring the safety of the operator.

Furthermore, if the control unit 21 receives any of the abnormal current detection signals E1-E10 and determines that an abnormal current has been detected in any of the charged spray heads 32, it may stop applying voltage to all charged spray heads 32. To perform this simultaneous stop control, a switch circuit 77 is provided in the line between the earth cable 24b and the current detection resistor 78, and the signal cable 26e from the selection circuit 72 is connected to the switch circuit 77 via a signal line separate from the switch circuit 75. In this case, the selection circuit 72 outputs an OFF activation signal to all switch circuits 75 and 77 in response to a control signal from the control unit 21, turning them off and thereby stopping the application of high voltage to all charged spray heads 32.

[d. Fire extinguishing agent supply section]
The extinguishing agent supply unit 16 shown in Fig. 1 will be described in more detail. The extinguishing agent supply unit 16 supplies, for example, fire-extinguishing water as an extinguishing agent to the charged water particle discharge unit 10. While the configuration and structure thereof are arbitrary, as an example, since the charged water particle spraying system of this embodiment is mounted on a ladder fire truck, the extinguishing agent supply unit 16 is configured as a pressurized water supply device or pressurized water supply facility including a fire pump provided on the fire truck. In this case, water sources include a water tank mounted on the fire truck and a fire hydrant connected to a hose. The extinguishing agent supply unit 16 is operated by operating the discharge start/stop switch on the control panel 14 to start and stop the supply of fire-extinguishing water.

The water supply pipe 22 from the extinguishing agent supply unit 16 branches off at the connection point with the charged water particle discharge unit 10 and is connected via an on-off valve 35 to multiple charged spray heads 32 provided in the charged water particle generation unit 30 of the charged water particle discharge unit 10. Furthermore, when the charged water particle spraying system is mounted on a ladder fire truck, the water supply pipe 22 is equipped with a known expandable piping structure in the ladder section of the ladder fire truck that expands and contracts according to the length of the ladder.

Each on-off valve 35 provided corresponding to the charged spray head 32 is connected to a separate signal cable 26d from the control unit 21, and is driven to open and close individually in response to control signals from the control unit 21. The control unit 21 controls the amount of charged water particles sprayed from the multiple charged spray heads 32, for example, based on operation by an operator. The method for adjusting the amount of spray is arbitrary, but for example, the amount sprayed from the charged spray head 32 can be adjusted by changing the number of on-off valves 35 that are driven open, or by changing the amount of fire-extinguishing water supplied from the fire extinguishing agent supply unit 16.

[e. Charge polarity switching control of charged water particles]
A more detailed description will be given below of the charge polarity switching control of the charged water particles contained in the charged water particle airflow emitted from the charged water particle emitting unit 10. The charge polarity switching control of the charged water particles contained in the charged water particle airflow emitted from the charged water particle emitting unit 10 is performed by the suction device 82, the smoke detector 80, and the control unit 21 of the operation panel 14 shown in FIG.

[f. Suction device]
The suction device 82 will be described in more detail. The suction device 82 sucks in a particulate mixture containing smoke particles from a fire from the fire compartment side toward the smoke detector 80, and while the structure and function thereof are optional, for example, as shown in Figure 6, it is composed of a sampling pipe 84, tubes 85 and 86, a suction pump 88, a rod member 90, a support 92, and a weight 94. Of these, the rod member 90, the support 92, and the weight 94 hold the sampling pipe 84 and the tube 85 movably.

(f1. Sampling tube)
The sampling pipe 84 will now be described in more detail. The sampling pipe 84 is a hollow member that sucks in the particulate air-fuel mixture in the fire compartment of the building from a suction port 84a at its tip. Since it is inserted into the fire compartment, it must be heat-resistant, for example, a metal pipe that can withstand the heat of a fire, and is further insulated from the supporting rod member 90 and the connected tube 85 so as to be in a non-grounded state. The diameter and length of the sampling pipe 84 are optional, but the diameter is set to, for example, about 2 to 3 cm and the length to about 1 to 2 m so that the operator can suck in the particulate air-fuel mixture from the suction port 84a at the tip of the sampling pipe 84 while maintaining a safe distance from the fire compartment.

(f2. Tube)
The tube 85 will be described in more detail below. The tube 85 is a flexible hollow member that connects the sampling pipe 84 to the inlet of the smoke detector 80, and may have any structure or material, but may be, for example, a flexible tube or hose made of synthetic resin or rubber.

A heating section 85a is provided at one end of the tube 85 that connects to the inlet of the smoke detector 80. The heating section 85a heats the space inside the tube 85 through which the particulate mixture drawn from the sampling tube 84 passes, in order to suppress or prevent condensation on the inner wall of the tube as the particulate mixture is drawn in. The heating section 85a has any structure and function, but may, for example, be a self-regulating heater wire that generates heat when electricity is applied and wrapped around the tube 85.

The particulate mixture drawn into the sampling tube 84 from the fire compartment is hot, and contains water vapor in addition to particulates (smoke particles). The high-temperature particulate mixture drawn in is cooled as it passes through the sampling tube 84 and tube 85, which can cause condensation on the inner walls of the tube. When condensation forms on the inner walls of tube 85, the particulates in the drawn particulate mixture are attracted to the water droplets on the inner walls, resulting in a partial loss of the particulates contained in the particulate mixture. Therefore, by providing a heating section 85a to heat the tube 85, condensation caused by the cooling of the particulate mixture is suppressed or prevented, allowing the particulate mixture to reach the inlet of the smoke detector 80 without losing any of its contained particulates, thereby improving the accuracy of identifying the type of smoke or fire based on the particulate mixture.

In this embodiment, a heating unit 85a is provided on the end of the tube 85 that connects to the smoke detector 80, but any suitable location may be used as long as condensation can be suppressed or prevented. Similarly, a heating unit may also be provided on the sampling pipe 84 to suppress or prevent condensation on the inner wall of the sampling pipe 84.

(f3. Suction pump)
The suction pump 88 will be described in more detail. The suction pump 88 has a suction port connected to the outlet of the smoke detector 80 via a tube 86, sucks in the particulate mixture via a sampling pipe 84 and a tube 85, and exhausts the particulate mixture that has passed through the smoke detector 80 to the outside. The suction pump 88 may have any structure or function, but may be an appropriate pump such as an axial flow pump that is driven by a motor to suck in and exhaust gas. The tube 86 may have any structure or material, but may be a tube, hose, or the like made of synthetic resin or rubber, similar to the tube 85 described above.

(g. Holding device)
The holding device is described in more detail below. The holding device movably holds the sampling tube 84 and the tube 85 so that the suction port 84a of the sampling tube 84 is inserted into the particulate mixture generated in the fire compartment. The structure and function of the holding device are arbitrary, but it may be composed of, for example, a rod member 90, a support 92, and a weight 94.

The rod member 90 is a long member that holds the sampling tube 84 and tube 85 in the extension direction of the tube 85. Its structure and function are arbitrary, but it may be, for example, a metal rod or pipe that is rigid in the front-to-rear direction, which is the extension direction of the tube 85. Its length is also arbitrary, but may be approximately 2 to 3 meters. Furthermore, the rod member 90 is positioned so that the tip of the rod member 90 is positioned on the outer periphery of the suction port 84a side of the sampling tube 84 when the tube 85 is fully retracted. While holding the sampling tube 84 and tube 85 in this state, when the tube 85 is extended, the tip of the rod member 90 moves around the outer periphery of the sampling tube 84 in the extension direction while maintaining its holding state of the sampling tube 84 and tube 85.

Furthermore, if the tip of the rod member 90 is also inserted into the fire compartment depending on the insertion depth of the sampling tube 84 into the fire compartment, the rod member 90 should be made of a heat-resistant material similar to the sampling tube 84. Furthermore, rather than being made of a material that is rigid in the extension direction of the tube 85, the rod member 90 may be made of a flexible material, with the contact point between the tip of the rod member 90 and the outer periphery of the suction port 84a side of the sampling tube 84 fixed, and the rod member 90 may be designed to extend (retract) in accordance with the extension (retraction) of the tube 85.

The support portion 92 movably supports the rod member 90, allowing the position of the sampling pipe 84 and tube 85 held by the rod member 90 to be adjusted so that the intake port 84a of the sampling pipe 84 can be positioned at any position corresponding to the fire compartment.

The structure and mechanism of the support portion 92 are arbitrary, but for example, it may be a three-dimensional swivel structure. A mechanism for realizing this three-dimensional swivel structure may involve, for example, placing a fixed base 92a above the blower 28, and erecting a support shaft portion 92b, which serves as a vertical support shaft, on the fixed base 92a. At its upper end, the support shaft portion 92b supports, for example, a U-shaped support portion 92c, which detachably supports the rod member 90, so that it can rotate freely around the support shaft (left and right), and also around a horizontal axis (up and down) positioned at the height of the support portion 92c in the left and right direction perpendicular to the support shaft.

By supporting the rod member 90 on the support portion 92c of the bearing portion 92, the rod member 90 can move not only in the forward/backward direction, which is its extension direction, but also left/right and up/down. This allows the tip of the rod member 90, which is located on the fire compartment side and is positioned on the outer periphery of the sampling tube 84, to be rotated left/right and up/down. This allows the position of the suction port 84a of the sampling tube 84 to be adjusted in all directions, including up/down, left/right, and forward/backward.

In addition, a weight 94 is disposed on the rear end of the rod member 90. The weight 94 is set so that the force moment at the tip end of the rod member 90, which holds the sampling pipe 84 and tube 85, with the support 92 as the fulcrum, is approximately equal to the force moment at the rear end where the weight 94 is disposed, thereby balancing the rod member 90 so that it remains horizontal.

Furthermore, the movement of the pole member 90 in the extension direction may be achieved by, for example, moving a basket 128 at the tip of an extendable ladder 126 shown in FIG.

[h. Smoke detector]
The smoke detector 80 will now be described in more detail. The smoke detector 80 identifies the type of smoke or fire based on the particulate mixture generated in the fire compartment sucked in by the suction device 82, and although the configuration and function thereof are arbitrary, for example, as shown in the cross-sectional structure of the smoke detector 80 viewed from the left in Fig. 6 in Fig. 7(A), it is composed of a smoke detection unit 100 formed in a smoke detection housing 96 and a detection circuit unit 106 housed in a case 104. Note that the detection circuit unit 106 disposed in the case is actually mounted on a circuit board or the like.

(h1. Smoke detection department)
The smoke detector 100 will be described in more detail. The smoke detector 100 is a space shielded from external light and formed within the smoke detector housing 96, through which the particulate mixture 102 sucked from the fire compartment by the suction device 82 passes. The smoke detector housing 96 may have any structure or shape. As an example, as shown in FIG. 7B, which is a cross-section taken along line x-x in FIG. 7A, the smoke detector housing 96 is provided with an inlet 96a and an outlet 96b for allowing the particulate mixture 102 sucked by the suction device 82 to pass through the smoke detector 100. The smoke detector housing 96 is generally cylindrical, with flattened upper and lower sides where the smoke detector 100 is located. While FIG. 7 shows the cylindrical smoke detector housing 96, the shape is not limited to a cylindrical shape. The cross-sectional shape of the cylinder may be polygonal, elliptical, or the like, as long as it allows the particulate mixture 102 to pass through the smoke detector 100.

The smoke detector 100 is configured with a first light-emitting element 108, a second light-emitting element 110, and a light-receiving element 112, all of which are arranged in a planar configuration with their respective optical axes 108a, 110a, and 112a aligned in the same plane.

The first light-emitting element 108 is, for example, a near-infrared LED, and emits light with a first wavelength λ1 of 600 nm or more, for example, λ1 = 900 nm. Furthermore, the first light-emitting element 108 has a first scattering angle θ1 of the optical axis 108a relative to the optical axis 112a of the light-receiving element 112, which is set to a predetermined angle in the range of 20° to 70°, for example, θ1 = 30°.

The second light-emitting element 110 is, for example, a visible light LED, and emits light with a center wavelength of 500 nm or less, for example, λ2 = 500 nm, as light with a second wavelength λ2. The second light-emitting element 110 also sets the second scattering angle θ2 of the optical axis 110a relative to the optical axis 112a of the light-receiving element 112 to a predetermined angle in the range of 110° to 160°, greater than the first scattering angle θ1, for example, θ2 = 120°.

The light-receiving element 112 is, for example, a photodiode sensitive to light from the infrared region to the visible light region. The first light-emitting element 108 and the second light-emitting element 110 can be driven to emit light in any manner, but for example, they can be driven to emit light alternately at a predetermined interval. When the first light-emitting element 108 emits light of a first wavelength λ1 and irradiates the particulate mixture flowing into point P, forward scattered light from the particulates (smoke particles) corresponding to a first scattering angle θ1 enters and is received by the light-receiving element 112, which then outputs a first signal as a light-receiving signal. Subsequently, when the second light-emitting element 110 emits light of a second wavelength λ2 and irradiates the particulate mixture flowing into point P, backscattered light from the particulates (smoke particles) corresponding to a second scattering angle θ2 enters and is received by the light-receiving element 112, which then outputs a second signal as a light-receiving signal.

In another embodiment of the smoke detector 100, one light-emitting element and two light-receiving elements may be used. In this case, the light-receiving element 112 in FIG. 7(B) is replaced with a single light-emitting element, such as a white LED, that emits light with a first wavelength λ1=900 nm and a second wavelength λ2=500 nm. The first light-emitting element 108 is replaced with a first light-receiving element that receives light with a first wavelength λ1=900 nm. The second light-emitting element 110 is replaced with a second light-receiving element that receives light with a second wavelength λ2=500 nm. The light-emitting element is then driven to emit light, and the first light-receiving element receives forward-scattered light with a first wavelength λ1=900 nm and a first scattering angle θ1=30° to output a first signal. The second light-receiving element receives back-scattered light with a second wavelength λ2=500 nm and a second scattering angle θ2=120° to output a second signal.

(h2. Detection circuit section)
The detection circuit unit 106 will be described in more detail. The detection circuit unit 106 identifies the type of smoke or fire based on the first and second signals obtained as light-receiving signals from the smoke detector unit 100, and may have any function or configuration, but may be composed of a control unit 114, a light-emitting driver unit 116, and a light-receiving amplifier unit 118, as shown in Fig. 8, for example. The control unit 114 is composed of a computer circuit equipped with a CPU, memory, and various input/output ports, and has the functions of a signal detection unit 120 and an identification unit 122 as functions realized by executing a program.

(h3. Signal detection unit)
The signal detection unit 120 will be described in more detail. The signal detection unit 120 outputs a drive signal to the light emission drive unit 116. Upon receiving the drive signal, the light emission drive unit 116 alternately drives the first light emitting element 108 and the second light emitting element 110 to emit light, for example, at predetermined intervals, to alternately irradiate the particulate mixture with light of the first wavelength λ1 and the second wavelength λ2, causing the particulate mixture to generate scattered light at the first scattering angle θ1 and the second scattering angle θ2. The signal detection unit 120 also receives a first signal obtained by receiving forward scattered light of the first wavelength λ1 at the first scattering angle θ1 with the light receiving element 112, and a second signal obtained by receiving backscattered light of the second wavelength λ2 at the second scattering angle θ2, and amplifies these signals using the light receiving amplifier 118. The signal detection unit 120 then detects a first detection value A1 and a second detection value A2 corresponding to the particulate concentration (smoke concentration) of the particulate mixture based on the first and second signals.

(h4. Identification unit)
The identification unit 122 will be described in more detail. The identification unit 122 identifies the type of smoke or the type of fire based on the comparison result between the first detection value A1 and the second detection value A2 detected by the signal detection unit 120. The identification unit 122 calculates, for example, a ratio R = A1/A2 between the first detection value A1 and the second detection value A2 as the comparison result, and identifies the fire as being cellulose-based smoke or a wood fire generating such smoke if the ratio R satisfies a predetermined cellulose-based identification condition, or identifies the fire as being hydrocarbon-based smoke or an oil fire generating such smoke if the ratio R satisfies a predetermined hydrocarbon-based identification condition.

The identification of smoke (fire) by the identification unit 122 will be explained in more detail. When light is irradiated onto the particulate mixture that has flowed into the smoke detector unit 100 in Figure 7(B), the scattered light is Mie scattering if the size (particle diameter) of the particulates (smoke particles) is equal to or greater than the wavelength of light, and is Rayleigh scattering if the size (particle diameter) of the smoke particles is smaller than the wavelength of light. As is well known, with Mie scattering, the forward scattered light is larger than the backward scattered light, and the larger the particle diameter, the greater the forward scattering. With Rayleigh scattering, the forward scattered light and backward scattered light are evenly distributed and are minimized at a scattering angle of 90°. Since smoke particles generally distribute around the wavelength of the irradiated light, the light scattering is a composite scattering that combines Mie scattering and Rayleigh scattering, and at least the characteristic of Mie scattering, in which the forward scattered light is larger than the backward scattered light, is exhibited.

For this reason, based on the difference in scattering efficiency, there is a relationship A1 > A2 between the first detection value A1 of forward scattered light received at a first scattering angle θ1 = 30° when irradiated with light of a first wavelength λ1 = 900 nm and the second detection value A2 of backward scattered light received at a second scattering angle θ2 = 120° when irradiated with light of a second wavelength λ2 = 500 nm, i.e., the forward scattered light is greater than the backward scattered light.

Furthermore, because the particle diameters of the particles (smoke particles) contained in cellulose-based smoke and hydrocarbon-based smoke that pass through the smoke detector 100 as a particulate mixture are different, the first detection value A1 and second detection value A2 detected will differ depending on the type of smoke. The type of smoke (fire) can be identified by comparing the ratio R obtained from the first detection value A1 and the second detection value A2 with predetermined cellulose-based identification conditions and hydrocarbon-based identification conditions. Any method can be used to identify the type of smoke (fire). For example, the signal detector 120 reads the first and second signals from the light receiving amplifier 118 through A/D conversion synchronized with the light emission drive timing of the first light-emitting element 108 and the second light-emitting element 110, and determines the ratio R from the first detection value detected from the first signal received at a predetermined timing and the second detection value A2 detected from the second signal received at the following timing to identify the type of smoke (fire).

Here, when the particulate mixture is cellulose-based smoke, the particle diameter of the smoke particles contained in the smoke is concentrated at, for example, 2 to 3 μm. Furthermore, when the particulate mixture is hydrocarbon-based smoke, the particle diameter of the smoke particles contained in the smoke is smaller than that of the smoke particles contained in cellulose-based smoke, concentrated at, for example, 1 to 2 μm. Therefore, the ratio R of the first detection value A1 to the second detection value A2 for smoke particles contained in hydrocarbon-based smoke, which have a large particle diameter, is, for example, R = 8.0. In contrast, the ratio R of the first detection value A1 to the second detection value A2 for smoke particles contained in cellulose-based smoke, which have a small particle diameter, is, for example, R = 2.3.

For this reason, there is a sufficient difference in the ratio R of the first detection value A1 to the second detection value A2 between cellulose-based smoke and hydrocarbon-based smoke. By setting the first discrimination threshold Rth1 for distinguishing between cellulose-based smoke (wood fire) and hydrocarbon-based smoke (oil fire) to a value in the range of 5 to 6, for example Rth1 = 5, it is possible to distinguish between cellulose-based smoke (wood fire) if the ratio R is Rth1 or greater, and between hydrocarbon-based smoke (oil fire) if the ratio R is less than Rth1.

The following explanation assumes that the type of smoke is identified using the identification unit 122.

[i. Types of smoke and charge polarity of charged water particles]
The relationship between the charge polarity of the charged water particles contained in the charged water particle airflow 12 emitted from the charged water particle emitting unit 10 and the type of smoke will be described in more detail below.

According to the inventor's findings, it has been experimentally confirmed that in order to achieve high smoke removal performance, there is a specific correspondence between the type of smoke and the charge polarity of the charged water particles.

(i1. Charge polarity of water particles relative to cellulosic smoke)
In experiments, when the spraying of positively charged water particles against cellulose-based smoke was compared with the spraying of negatively charged water particles, the time from the start of spraying the charged water particles until the smoke concentration decreased to a predetermined level was shorter when negatively charged water particles were sprayed than when positively charged water particles were sprayed, and negatively charged water particles provided higher smoke elimination performance.

(i2. Charge polarity of water particles relative to hydrocarbon smoke)
Furthermore, when comparing the spraying of positively charged water particles against hydrocarbon smoke with the spraying of negatively charged water particles, the time from the start of spraying the charged water particles until the smoke concentration drops to a predetermined level is almost the same, and no difference in smoke suppression performance is observed depending on the charge polarity of the charged water particles.However, it has been found that when negatively charged water particles are sprayed, smoke suppression performance is not impaired even if the amount sprayed is reduced.

(i3. Initial setting of charging polarity of charged water particles)
It may take time for the smoke detector 80 of this embodiment to identify the type of smoke based on the particulate mixture generated in the fire compartment and for the control unit 21 to switch and control the charge polarity of the charged water particles, so it is necessary to initially set a predetermined charge polarity for the charged water particles. In this case, as described above, charging the charged water particles with a negative polarity improves the smoke suppression performance for cellulose-based smoke, and there is no difference in smoke suppression performance between negative and positive polarities for hydrocarbon-based smoke, so it is preferable to initially set the charge polarity of the charged water particles to a negative polarity.

Therefore, the control unit 21 is initially configured to negatively charge the charged water particles contained in the charged water particle airflow 12 released into the fire compartment. During the release of the charged water particle airflow 12 containing negatively charged charged water particles according to the initial configuration, if the smoke detector 80 identifies cellulose-based smoke, the control unit 21 maintains the initially configured negative charging polarity, which provides excellent smoke suppression performance. On the other hand, if the smoke detector 80 identifies hydrocarbon-based smoke, any polarity can be used because there is no difference in smoke suppression performance depending on the charging polarity of the charged water particles. If the charged water particles are configured to be positively charged, the control unit 21 controls the charging polarity to be switched from the initially configured negative polarity to a positive polarity. In addition to controlling the switching of charging polarity, the control unit 21 may also control the spray amount from the charged spray head 32 and the charge amount of the charged water particles depending on the type of smoke.

Here, initially setting the charged water particles to a negative polarity means that the high-voltage power supply 18 applies a high voltage to the charged spray head 32 so that the potential of the induction electrode section 60 of the charged spray head 32 is positive relative to the potential of the water-side electrode section 62 by starting the discharge of the charged water particle airflow 12, without requiring an operator to set the polarity of the charged water particles.

[j. Control panel]
The control panel 14 shown in Figure 1 will be described in more detail below. The control panel 14 is an operation unit that allows an operator to operate the charged water particle spraying system of this embodiment, and the operations that can be performed on the control panel 14 are arbitrary, but examples include starting and stopping the charged water particle discharge unit 10, adjusting the discharge direction of the charged water particle airflow 12 from the charged water particle discharge unit 10 and adjusting the spray amount from each charged spray head 32, selecting the type of voltage to be applied by the high-voltage power supply unit 18, adjusting the voltage, and switching the polarity.

The operation panel 14 is provided with an operation display unit 20 and a control unit 21. The operation display unit 20 is provided with various operation buttons, operation levers, displays, indicator lights, etc. required for remote operation of the charged water particle emitter 10. The control unit 21 outputs control signals based on operations by the operator via the operation display unit 20, and controls the charged water particle emitter 10, etc. Its functions and configuration are arbitrary, but it may be composed of a computer circuit equipped with a CPU, memory, various input/output ports, etc., for example, and the specified control functions are realized by the CPU executing a program.

[k. Ladder fire engine equipped with an electrocharged water particle spray system]
Fire and smoke extinguishing using a ladder fire truck equipped with the charged water particle spraying system of this embodiment will be described in more detail. Figure 9 is an explanatory diagram showing an example of fire and smoke extinguishing work at a fire scene using a ladder fire truck equipped with the charged water particle spraying system of this embodiment. The charged water particle discharge unit 10, smoke detector 80, and suction device 82 shown in Figure 1 are mounted on a basket 128 at the tip of an extendable ladder 126, and the control panel 14, extinguishing agent water supply unit 16, and high-voltage power supply unit 18 are mounted on the ladder fire truck 124 side.

For example, if a fire breaks out on the third floor of a building 130 , a ladder fire truck 124 that arrives at the fire scene extends its ladder 126 so that the charged water particle discharger 10 attached to the basket 128 approaches an exterior wall opening such as a window of the building. Subsequently, by performing a discharge activation operation on the control panel 14 to discharge the charged water particle airflow 12, fire-extinguishing water is supplied from the extinguishing agent water supply unit 16 to the charged water particle discharger 10, a high voltage is applied from the high-voltage power supply unit 18 to the charged water particle discharger 10, and the air blower 28 is activated by a control signal from the control panel 14. As a result, the airflow from the air blower 28 contains negatively charged water particles sprayed from the charged spray head 32 in accordance with the initial setting, and the charged water particle airflow 12 is discharged toward the fire compartment 132.

Furthermore, when the ladder 126 is extended and the charged water particle discharger 10 attached to the basket 128 is brought close to an exterior wall opening such as a window of the building, the sampling tube 84 of the suction device 82 arranged on top of the charged water particle discharger 10 is inserted into the particulate mixture containing smoke particles from the fire occurring in the fire compartment 132, and the particulate mixture is sucked in by the suction device 82 so that it reaches the smoke detector 80, which then identifies the type of smoke based on the particulate mixture. As mentioned above, the position of the sampling tube 84 can be adjusted in the forward/backward, left/right, and up/down directions, so an operator standing on the basket 128 can adjust the insertion position of the sampling tube 84.

Furthermore, after the release of the charged water particle airflow 12 has begun, the operator can operate the control panel 14 to adjust the direction of the charged water particle airflow 12 up and down and/or left and right, thereby adjusting the direction in which the charged water particle airflow 12 is released toward the fire compartment 132. Furthermore, the control unit 21 switches and controls the charge polarity of the charged water particles so that the voltage polarity of the voltage applied by the high-voltage power supply unit 18 satisfies conditions corresponding to the type of smoke identified by the smoke detector 80.

In addition, depending on the situation regarding fire extinguishing and smoke suppression due to the release of the charged water particle airflow 12, the operator will adjust the release direction of the charged water particle airflow 12, adjust the applied voltage using the high-voltage power supply unit 18, and switch the applied voltage polarity, and release the charged water particle airflow 12 containing charged water particles with the charge amount and charge polarity appropriate for fire extinguishing and smoke suppression at the fire site into the fire compartment 132 to perform fire extinguishing, fire prevention, and smoke suppression.

[l. Control operation of the charged water particle spraying system]
An example of the control operation of the charged water particle spraying system by the control unit 21 will be described in more detail with reference to the flowchart of FIG.

When the charged water particle spray system is started, the control unit 21 of the operation panel 14 shown in Figure 1 performs the control operation shown in Figure 10. The charged water particles contained in the charged water particle airflow 12 released into the hydrocarbon smoke are set to be positively charged.

In Figure 10, the control unit 21 initially sets the polarity of the charged water particles contained in the charged water particle airflow 12 to be released to a negative polarity in step S1. When a release start command is received in step S2, such as by an operator operating the control panel 14 to start release, the process proceeds to step S3, where the extinguishing agent supply unit 16 is activated to supply an extinguishing agent, such as fire-extinguishing water, to the multiple charged spray heads 32 provided in the charged water particle release unit 10. In step S4, the water particles are negatively charged according to the initial setting, and the charged water particle airflow 12 containing negatively charged charged water particles is released toward the fire compartment.

Next, in step S5, the control unit 21 determines whether hydrocarbon smoke has been identified by the smoke detector 80. If hydrocarbon smoke has been identified, the control unit 21 proceeds to step S6, where it switches the charge polarity of the charged water particles to positive polarity and releases the charged water particle airflow 12. Furthermore, if the charge polarity of the charged water particles is already positive, no switching control is performed.

On the other hand, if step S5 determines that the smoke is not hydrocarbon-based, i.e., that the smoke is cellulose-based, the process proceeds to step S7, where the charge polarity of the charged water particles is switched to negative and the charged water particle airflow 12 is emitted. However, when step S7 is first executed, the water particles are initially charged to negative polarity in step S4, so no switching control is performed to maintain the negative charge polarity.

Next, if the control unit 21 determines in step S8 that the spray amount from the charged spray heads 32 has been changed due to an operation by the operator or the like, the control unit 21 proceeds to step S9, where it selects the number of charged spray heads 32 to spray by selectively opening and closing the on-off valves 35 shown in FIG. 5, and changes the spray amount. The change in the spray amount from the charged spray heads 32 may also be adjusted by changing the amount of extinguishant supplied to the charged spray heads 32 from the extinguishant supply unit 16.

Next, if the control unit 21 determines in step S10 that the charge amount of the charged water particles has been changed due to an operation by the operator or the like, it proceeds to step S11 and adjusts the voltage applied from the high-voltage power supply unit 18 to the charged spray head 32 to change the charge amount of the charged water particles.

The control unit 21 then proceeds to step S12. If the abnormal current detection circuit 74 shown in FIG. 4 determines that an abnormal current due to poor insulation has been detected in any of the multiple charged spray heads 32, the control unit 21 proceeds to step S13 and performs application stop control to stop the application of high voltage to the charged spray head 32 in which the abnormal current has been detected. Note that this application stop control may also stop the application of high voltage to all heads, including the charged spray head 32 in which the abnormal current has been detected.

The control unit 21 then proceeds to step S14 and repeats the process from step S5 until it determines that a release termination command has been issued by an operator or other means. Once a release termination command has been issued, it proceeds to step S15 and performs a predetermined release termination process to stop the release of the charged water particle airflow 12, and then terminates the process.

[m. Modifications of the present invention]
(fire engine)
Although the above embodiment illustrates an example in which the charged water particle spraying system is mounted on a ladder fire truck, the system may be mounted on any suitable fire truck as long as the charged water particle discharger 10 can be brought close to a fire compartment located at a high point in a building from the outside. For example, the charged water particle discharger 10 may be provided on an elevated work platform in a fire truck for high-altitude work, or on the tip of a boom-equipped fire truck. Furthermore, the charged water particle discharger 10 may be mounted on a tracked vehicle, which may be remotely operated to move to a fire compartment that is inaccessible to humans and inject an airflow of charged water particles.

(High voltage supply unit)
In the above embodiment, a DC voltage is applied from the high-voltage power supply 18 between the induction electrode 60 and the water-side electrode 62 of the charged fine spray head 32, but other voltages such as a pulse voltage, a pulsating voltage, and an AC voltage may also be applied. Also, when applying a voltage between the induction electrode 60 and the water-side electrode 62 from the high-voltage power supply 18, voltage adjustment and voltage polarity switching are possible, but this is not limited to this and is optional; for example, the applied voltage and/or voltage polarity may be fixed.

(others)
The present invention is not limited to the above-described embodiment, but includes appropriate modifications that do not impair the objects and advantages thereof, and is not limited by the numerical values shown in the above-described embodiment.

[n. Note]
Here, the features of the charged water particle spraying system according to the embodiment of the present invention can be summarized as follows: Features 1 to 6.

(Feature 1)
A charged water particle spraying system that identifies a type of smoke or a type of fire and sprays charged water particles to a target area under spraying conditions according to the identification result,
a plurality of electrostatic spray heads for spraying electrostatically charged water particles;
a smoke detector that identifies the type of smoke or fire based on the particulate mixture generated in the target area;
a control unit that controls conditions for spraying the charged water particles according to the type of smoke or the type of fire identified by the smoke detector;
The present invention is characterized by the following features.

(Feature 2)
2. The charged water particle spraying system according to claim 1,
The smoke detector distinguishes between the type of smoke produced by burning cellulose-based materials and the smoke produced by burning hydrocarbon-based materials.
The control unit is characterized by dispersing the charged water particles under dispersal conditions according to the results of the identification of smoke generated when a cellulose-based material is burned or smoke generated when a hydrocarbon-based material is burned, as identified by the smoke detector.

(Feature 3)
Feature 2: The charged water particle spraying system,
The control unit is characterized in that if the smoke detector identifies smoke resulting from the burning of a cellulose-based material, the control unit charges the charged water particles to a negative polarity and sprays them, and if the smoke detector identifies smoke resulting from the burning of a hydrocarbon-based material, the control unit charges the charged water particles to either a positive polarity or a negative polarity and sprays them.

(Feature 4)
2. The charged water particle spraying system according to claim 1,
The smoke detector identifies the type of fire, wood or oil,
The control unit is characterized by dispersing the charged water particles under dispersal conditions according to the result of the discrimination of a wood fire or an oil fire discriminated by the smoke detector.

(Feature 5)
Feature 4: The charged water particle spraying system,
The control unit is characterized in that if the smoke detector identifies a wood fire, the charged water particles are negatively charged and dispersed, and if the smoke detector identifies an oil fire, the charged water particles are positively charged and dispersed.

(Feature 6)
The charged water particle spraying system according to Features 1 to 5,
The control unit is characterized by controlling the amount of charge or the amount of scattering of the charged water particles according to the type of smoke or type of fire identified by the smoke detector.

10: Charged water particle emission section 12: Charged water particle airflow 14: Operation panel 16: Fire extinguishing agent supply section 18: High-voltage power supply section 20: Operation display section 21: Control section 22: Water supply pipe 24: High-voltage cable 24a: Voltage application cable 24b: Earth cables 26a to 26f: Signal cable 28: Air blower section 30: Charged water particle generation section 31: Support ring 32: Charged spray head 34: Axial fan 35: On-off valve 36: Fan motor 38: Protective cover 40: Stand 42: Rotation support section 44: Left-right direction adjustment section 46: Left-right rotation shaft 48: Up-down direction adjustment section 50: Up-down rotation shaft 52: Center of gravity 54: Body 56: Spray nozzle section 58: Electrode holding section 60: Induction electrode section 62: Water side electrode section 64: Water supply connection section 66: High-voltage Voltage variable circuit 68: polarity reversal circuit 72: selection circuit 74: abnormal current detection circuits 75, 77: switch circuit 76: current limiting resistor 78: current detection resistor 80: smoke detector 82: suction device 84: sampling pipe 84a: suction ports 85, 86: tube 85a: heating section 88: suction pump 90: rod member 92: support section 94: weight 96: smoke detector housing 100: smoke detector section 102: particulate gas mixture 104: case 106: detection circuit section 108: first light-emitting element 110: second light-emitting element 112: light-receiving element 114: control section 116: light-emitting driver section 118: light-receiving amplifier section 120: signal detection section 122: identification section 124: ladder fire engine 126: ladder 128: basket 130: building 132: fire compartment

Claims (5)

Identifying the type of smoke or fire, and spraying the charged water particles to the target area under spraying conditions according to the identification result ;
identifying the type of smoke as either cellulose-based smoke or hydrocarbon-based smoke, and dispersing the charged water particles under dispersal conditions according to the result of the identification of cellulose-based smoke or hydrocarbon-based smoke;
A charged water particle spraying system characterized in that if the identification result is cellulose-based smoke, the charged water particles are negatively charged and sprayed, and if the identification result is hydrocarbon-based smoke, the charged water particles are either positively or negatively charged and sprayed .
2. The charged water particle spraying system according to claim 1,
The system for spraying charged water particles is characterized by identifying the type of fire as either a wood fire or an oil fire, and spraying the charged water particles under spray conditions according to the results of the identification of the wood fire or the oil fire.
3. The charged water particle spraying system according to claim 2 ,
A charged water particle spraying system characterized in that, if the identification result is a wood fire, the charged water particles are charged negatively and sprayed, and if the identification result is an oil fire, the charged water particles are charged either positively or negatively and sprayed.
Identifying the type of smoke or fire, and spraying the charged water particles to the target area under spraying conditions according to the identification result;
The type of fire is identified as either a wood fire or an oil fire, and the charged water particles are sprayed under spray conditions according to the result of the identification of the wood fire or the oil fire;
A charged water particle spraying system characterized in that, if the identification result is a wood fire, the charged water particles are charged negatively and sprayed, and if the identification result is an oil fire, the charged water particles are charged either positively or negatively and sprayed.
5. The charged water particle spraying system according to claim 1,
A charged water particle spraying system, characterized in that the amount of the charged water particles to be sprayed or the amount of charge thereof is controlled according to the type of smoke or the type of fire.