JP3201403U - Facilities such as parking lots equipped with means for monitoring and discriminating the occurrence of hydrogen gas leakage - Google Patents

Abstract

To provide a facility such as a parking lot provided with means for monitoring and discriminating occurrence of hydrogen gas leakage and hydrogen flame. Hydrogen gas detection comprising a gas chromic metal thin film which absorbs and colors hydrogen atoms, and a catalytic metal thin film which is supported on the surface of the gas chromic metal film and adsorbs hydrogen gas H2 to dissociate into hydrogen atoms. An optical hydrogen gas detection switch X including an element, a gas container that transmits ultraviolet light and seals an inert gas, an anode that is hermetically disposed in the gas container, and an ultraviolet that is hermetically disposed in the gas container. At least of the hydrogen flame detector W comprising a cathode that emits photoelectrons to the anode by light, and a control means for detecting a hydrogen flame F based on a current flowing from the anode to the cathode by applying a pulse voltage between the anode and the cathode. Means for monitoring and discriminating the occurrence of leakage of hydrogen gas is provided. [Selection] Figure 12

Description

  The present invention relates to a parking lot having means for monitoring and discriminating occurrence of hydrogen gas leakage and hydrogen flame.

  Fuel cells that use hydrogen gas as fuel, and fuel cell vehicles have a risk of explosion due to hydrogen gas, and should be handled with care. Monitor hydrogen gas leaks in parking lots where fuel cell vehicles are parked. It needs to be detected.

As a technique for monitoring and discriminating hydrogen gas leakage, Patent Document 1 discloses a hydrogen gas detection sensor in which a pair of electrodes and a detection film are stacked on the surface of an insulating substrate, and a heater is provided on the back surface of the insulating substrate. Sensing film is a metal oxide which increases the catalyst for dissociating the adsorbed to protons (H ⁺⁾ and electrons (e) a hydrogen gas, an electrically conductive at a reaction of protons (H ⁺⁾ and electrons (e) Is done.

  On the other hand, Patent Document 2 discloses an infrared sensor as a technique for detecting a fuel flame. The infrared sensor detects a flame by sensing infrared rays emitted from a heat source of the flame. By using an infrared sensor, it is possible to detect a fire and take a quick response. As a result, it helps to prevent secondary disasters.

JP 2006-162365 A JP 10-139100 A

  When a hydrogen fuel cell vehicle equipped with a hydrogen fuel cell is parked in a facility such as a parking lot, it is necessary to detect an unexpected hydrogen gas leak from the hydrogen fuel cell. In addition, ignition of hydrogen gas leaked by lightning strikes on automobiles, sparks generated by vehicle inspection work, etc. may cause serious accidents such as explosions.

  However, in Patent Document 1, since the metal film is heated by a heater when detecting hydrogen gas, the metal film is deteriorated and the response and reliability of hydrogen gas detection are poor.

  Further, since the hydrogen flame is almost colorless and does not emit infrared rays, the infrared sensor of Patent Document 2 has a problem that it is difficult to detect the hydrogen flame.

  According to a first aspect of the present invention, there is provided a substrate, a gas chromic metal thin film that is formed on the surface of the substrate, and absorbs and colors hydrogen atoms, and is supported on the surface of the gas chromic metal thin film, and adsorbs hydrogen gas. A hydrogen gas detecting element dissociating into hydrogen atoms, a color identifying means for identifying a color of the gas chromic metal thin film, converting the identified color into a color electric signal, and outputting the color electric signal; And an optical hydrogen gas detection switch characterized by comprising a hydrogen discrimination means for discriminating hydrogen gas leak based on a change in electrical signal, and monitoring and discriminating the occurrence of hydrogen gas leak It is a facility such as a parking lot equipped with means to do this.

  According to a second aspect of the present invention, the hydrogen determination unit includes a signal storage unit that stores a reference color electrical signal indicating a color of the gas chromic metal thin film in an air atmosphere, and the reference color electrical signal from the color electrical signal. A signal calculation unit that calculates a difference electric signal by subtracting, a determination signal setting unit that sets a determination electric signal indicating a hydrogen gas concentration, and the difference electric signal and the determination electric signal are compared. 2. A facility such as a parking lot having a means for monitoring and discriminating the occurrence of hydrogen gas leak according to claim 1, further comprising a hydrogen leak discriminating unit that discriminates that hydrogen gas leaks when the electric signal is greater than or equal to the electric signal. It is.

  According to a third aspect of the present invention, the color identification means receives a light emitting element, a light projecting lens that irradiates the gas chromic metal thin film from the catalyst metal thin film with light emitted from the light emitting element, and receives visible light of three primary colors. A light receiving element that converts the light intensity of the visible light wavelengths of the three primary colors into the color electric signal and outputs the light, and a light receiving lens that collects light from the gaschromic metal thin film and introduces the light into the light receiving element. A facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to claim 1 or 2.

  According to a fourth aspect of the present invention, the substrate is a transparent substrate, and the light receiving lens condenses light transmitted through the transparent substrate from the gas chromic metal thin film. It is a facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage.

  According to a fifth aspect of the present invention, the color identification means includes a light-emitting side optical fiber element that transmits light emitted from the light-emitting element to the light projecting lens, and a light-receiving side that transmits light collected from the light-receiving lens to the light receiving element. A facility such as a parking lot provided with means for monitoring and discriminating occurrence of hydrogen gas leakage according to claim 3 or 4, characterized by comprising an optical fiber element.

Claim 6 according to the present invention comprises a gas container that transmits ultraviolet light and seals an inert gas;
A pulse voltage is applied between the anode and the cathode, an anode that is hermetically disposed in the gas container, a cathode that is hermetically disposed in the gas container, and emits photoelectrons to the anode by the ultraviolet light. And a control means for detecting the hydrogen flame based on a current flowing from the anode to the cathode, wherein the anode and the cathode are composed of an anode plate electrode and a cathode plate electrode, and the surface of each plate electrode is Oppositely arranged in parallel and spaced apart from the surface of each plate electrode, the anode has a plurality of electrode holes that open on the front and back surfaces of the anode plate electrode and penetrate the anode plate electrode. It is a facility such as a parking lot equipped with means for monitoring and discriminating the occurrence of hydrogen gas leakage, characterized by comprising a hydrogen flame detector.

  The facility such as a parking lot may be a parking lot with a roof, a three-dimensional parking lot, or a parking lot without a roof. The facility such as a parking lot may be a public parking lot or a private parking lot. Furthermore, the facility such as a parking lot may be a temporary parking space for a car at a gas station or a hydrogen gas station. In particular, in a private parking lot, when a home hydrogen fuel cell is installed, leakage of hydrogen gas from the home hydrogen fuel cell and generation of a hydrogen flame may be detected.

  Further, it is preferable that a plurality of optical hydrogen gas detection switches and hydrogen flame detectors provided in a facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage are provided. If a plurality of optical hydrogen gas detection switches are installed, it is possible to detect even when hydrogen gas leaks over a wide range. If a plurality of hydrogen flame detectors are installed, it is possible to detect hydrogen flames even if the direction of the vehicle parked in a facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage is different. .

According to the first aspect of the present invention, the color identifying means identifies the color of the gas chromic metal thin film, converts the identified color into a color electric signal, and outputs it to the hydrogen identifying means. In the hydrogen gas non-leakage (air atmosphere) and the hydrogen gas leak (hydrogen gas atmosphere), the color of the gas chromic metal thin film is different, and the color electric signals output from the color identification means are also different. Therefore, by monitoring the change in the color electrical signal by the hydrogen discrimination means, it is possible to determine the hydrogen gas leakage based on the change in the color electrical signal.
Thereby, according to Claim 1 which concerns on this invention, hydrogen gas non-leakage or hydrogen gas leak is optically detected only by identifying the color of a gas chromic metal thin film, without heating a hydrogen gas detection element. It is possible to suppress deterioration of the hydrogen gas detection element and improve the response and reliability of hydrogen gas detection in a facility such as a parking lot.
Note that “color” means color, light and shade, and “color” includes color, light and shade, and gloss.

According to claim 2 of the present invention, in addition to the effect of claim 1, hydrogen gas leakage in the parking lot can be determined by comparing the differential electric signal and the determination electric signal.
For the reference color electrical signal, a hydrogen gas detection element is placed at the hydrogen gas measurement point in the air atmosphere, the color of the gas clock metal thin film is identified by the color identification means, and the identification color in the air atmosphere is converted to the reference color electrical signal And can be stored in the signal storage unit. In the discrimination signal section, a discrimination electric signal can be set according to the hydrogen gas concentration.

  According to the third aspect of the present invention, in addition to the effects of the first and second aspects, the light receiving element has three primary colors that are reflected by the gas chromic metal thin film or three primary colors that are transmitted through the gas chromic metal thin film. Is received, and the light intensity of the visible light wavelengths of the three primary colors is converted into a color electric signal and output to the hydrogen discrimination means. Thereby, the hydrogen gas leakage in facilities, such as a parking lot, can be discriminate | determined based on the light intensity (color electrical signal) of the visible light wavelength which shows the color of a gas chromic metal thin film.

  According to the fourth aspect of the present invention, in addition to the effect of the third aspect, a hydrogen gas detection element is disposed between the light projecting lens and the light receiving lens, and the transparent substrate (substrate) is transmitted from the gaschromic metal thin film. Can be collected by the light receiving lens.

  According to the fifth aspect of the present invention, in addition to the effects of the third and fifth aspects, the light-emitting side optical fiber element and the light-receiving side fiber element include hydrogen gas together with the light projecting lens, the light receiving lens, and the hydrogen gas detecting element. The light emitting element, the light receiving element, and the hydrogen discrimination means can be arranged outside the hydrogen gas monitoring area. In the hydrogen gas monitoring area, there is a risk of explosion due to hydrogen gas leakage. By disposing and extending the light emitting side optical fiber element and the light receiving side optical fiber element in the hydrogen gas monitoring area, hydrogen gas leakage can be monitored and detected in a safe area away from the hydrogen gas monitoring area.

According to the sixth aspect of the present invention, the ultraviolet light emitted from the hydrogen flame passes through the gas container and enters (collises) the cathode. The cathode emits photoelectrons toward the anode by the photoelectric effect caused by the incidence of ultraviolet light. By applying a pulse voltage between the anode and the cathode, a discharge current flows from the anode toward the cathode. The control means detects (discriminates) the hydrogen flame based on the discharge current.
Thus, in claim 6 according to the present invention, the hydrogen flame can be detected by utilizing the discharge effect between the anode and the cathode due to the ultraviolet light of the hydrogen flame, and from the fuel cell and the fuel cell vehicle in the facility such as a parking lot. Even if a fire accident due to hydrogen occurs, it is possible to quickly shift to fire fighting activities (initial fire fighting activities) and prevent secondary disasters.
According to the sixth aspect of the present invention, since the anode and the cathode are constituted by the plate electrodes, sufficient photoelectrons can be emitted from the entire surface of the cathode plate electrode toward the entire surface of the anode plate electrode. Even if the interval is increased, the hydrogen flame can be detected with high sensitivity by passing a discharge current between the anode and the cathode. Further, since the anode plate electrode has a plurality of electrode holes, the ultraviolet light emitted from the hydrogen flame can enter the cathode plate electrode through each electrode hole without being blocked by the anode plate electrode.

It is a figure which shows the optical hydrogen gas detection switch of 1st Embodiment, Comprising: (a) is a schematic block diagram, (b) is a perspective view of a hydrogen gas detection element (hydrogen gas non-leakage). It is a figure which shows the apparatus housing | casing etc. which comprise the optical hydrogen gas detection switch of 1st Embodiment, (a) is a right view, (b) is an AA arrow line view of Fig.2 (a), (C) is BB sectional drawing of Fig.2 (a), (d) is CC arrow directional view of FIG.2 (b). It is a figure which shows the optical hydrogen gas detection switch of 1st Embodiment, Comprising: (a) is a schematic block diagram, (b) is a perspective view of a hydrogen gas detection element (hydrogen gas leak). It is a schematic block diagram which shows the optical hydrogen gas detection switch of 2nd Embodiment. It is a schematic block diagram which shows the optical hydrogen gas detection switch of 3rd Embodiment. It is a figure which shows the apparatus housing | casing etc. which comprise the optical hydrogen gas detection switch of 3rd Embodiment, (a) is a right view, (b) is the DD arrow directional view of Fig.6 (a), (C) is EE sectional drawing of Fig.6 (a), (d) is the FF arrow line view of FIG.6 (b). It is a general view which shows a hydrogen flame detector. It is a figure which shows the hydrogen flame detection means which comprises a hydrogen flame detector, Comprising: (a) is an AA arrow figure of FIG. 7, (b) is a BB cross-section arrow directional view of FIG. 8 (a). It is CC sectional view taken on the line of Fig.8 (a). It is the figure which has arrange | positioned the hydrogen flame detector in the joint vicinity of the hydrogen gas pipe line. It is a principal part enlarged view which shows the discharge effect of the hydrogen flame detection means (gas container, anode, cathode) by the ultraviolet light radiated | emitted from a hydrogen flame. It is a figure which shows the outline of facilities 201, such as a parking lot which concerns on this invention.

An optical hydrogen gas detection switch X installed in a facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage in the present invention will be described with reference to FIGS.
As specific forms of the optical hydrogen gas detection switch X, the optical hydrogen gas detection switches X1 to X3 of the first to third embodiments will be described.

<First Embodiment>
The optical hydrogen gas detection switch according to the first embodiment will be described with reference to FIGS.

  1 to 3, an optical hydrogen gas detection switch X1 (hereinafter referred to as “optical hydrogen gas detection switch X1”) of the first embodiment includes an apparatus housing 1, a hydrogen gas detection element 2, and a color identification means 3. , A hydrogen discrimination means 5 and an alarm means 6.

As shown in FIG. 2, the device housing 1 is formed in a rectangular box body by front and rear plates 11 and 12, left and right plates 13 and 14, a ceiling plate 15 and a bottom plate 16, and has an internal space K.
The apparatus housing 1 includes an opening window 17, a mounting table 18, and a net plate 19. The opening window 17 is formed in the right plate 14 and communicates with the internal space K and the outside of the apparatus housing 1. The mounting table 18 is disposed in the internal space K of the apparatus housing 1 and is fixed to the bottom body 15. The mesh plate 19 is disposed in the internal space K of the apparatus housing 1 and covers the opening window 17. The mesh plate 19 is fixed to the right plate 14 of the apparatus housing 1 so as to be removable.

  As shown in FIGS. 1 to 3, the hydrogen gas detection element 2 includes a substrate 21, a gas chromic metal thin film 22, and a catalyst metal thin film 23.

As shown in FIGS. 1 to 3, the substrate 21 is made of amorphous quartz glass (SiO ₂ ), a metal such as aluminum (Al) or iron (Fe), or a ceramic. As the substrate 21, for example, quartz glass is used as a transparent substrate.

As shown in FIGS. 1 to 3, the gas chromic metal thin film 22 occludes hydrogen atoms (H ⁺ : protons) and colors. The gas chromic metal film 22 is an oxide-based metal, which is molybdenum oxide (MoO _x ), tungsten oxide (WO _x ), tantalum oxide (TaO _x ), titanium oxide (TiO _x ), vanadium oxide (VO _x ). , Chromium oxide (CrO _x ), zirconia oxide (ZrO _x ), haonium oxide (HfO _x ) or yttrium oxide (YO _x ).
For example, a tungsten trioxide thin film (WO ₃ ) is used as the gaschromic metal thin film 22. When a tungsten trioxide thin film (WO ₃ ) occludes hydrogen atoms (H ⁺ ), it is colored (discolored) from light green (before occlusion of hydrogen atoms) to dark blue. The tungsten trioxide thin film is deposited (supported) on the surface of the substrate 21 by sputtering (for example, high frequency magnetron sputtering) of metallic tungsten in a reduced pressure oxidizing atmosphere of argon and oxygen.

As shown in FIGS. 1 to 3, the catalytic metal thin film 23 is supported (deposited) on the surface of the gas chromic metal thin film 22, adsorbs hydrogen gas (H ₂ : hydrogen molecules), and hydrogen atoms (H ⁺ : Dissociates into protons.
The catalytic metal thin film is platinum (Pt), palladium (Pd), nickel (Ni), rhodium (Rh), iridium (Ir) or ruthenium (Ru).
The catalytic metal thin film 23 can be supported (deposited) by a high frequency sputtering method, a direct current sputtering method, a molecular beam epitaxy method, or a vacuum deposition method. For example, the gas chromic metal thin film 22 is formed as a transparent thin film having a film thickness of 30 nm to 50 nm. It adheres on the surface of (tungsten oxide thin film).
As the catalytic metal thin film 23, for example, a platinum thin film (Pt) is used, and supported (deposited) on the surface of the tungsten trioxide thin film (WO ₃ ) by the above sputtering methods.

The hydrogen gas detection element 2 includes molybdenum oxide (MoO _x ), tungsten oxide (WO _x ), tantalum oxide (TaO _x ), titanium oxide (TiO _x ), vanadium oxide (VO _x ), chromium oxide (CrO _x ), and oxide. Any one gaschromic metal thin film 22 is selected from zirconia (ZrO _x ), haonium oxide (HfO _x ) or yttrium oxide (YO _x ), and platinum (Pt), palladium (Pd), nickel (Ni), rhodium One arbitrary catalytic metal thin film 23 is selected from (Rh), iridium (Ir), or ruthenium (Ru), and the selected gas chromic metal thin film 22 and the catalytic metal thin film 23 are configured.

  As shown in FIG. 2, the hydrogen gas detection element 2 is disposed in the internal space K of the apparatus housing 1. The hydrogen gas detection element 2 has a substrate 21 mounted on the mounting table 18 and is fixed to the mounting table 18 so as to be removable. The hydrogen gas detection element 2 is disposed with the catalytic metal film 23 (platinum thin film) facing the ceiling plate 15 of the apparatus housing 1.

The color identification means 3 identifies (discriminates) the color (color) of the gas chromic metal thin film 22 of the hydrogen gas detection element 2, converts the identified color into a color electric signal f1, and outputs it. Note that “color” means color, light and shade, and “color” includes color, light and shade, and gloss.
As shown in FIG. 1, the color identification unit 3 includes a color identification sensor (color sensor) and includes a light emitting unit 31 and a light receiving unit 32.

  The light emitting unit 31 includes a light projecting lens 33, a light emitting element 34, and a light emitting side optical fiber element 37.

  The light projecting lens 33 irradiates the gas chromic metal thin film 22 (tungsten trioxide thin film) with the light emitted from the light emitting element 34 (light) from the catalytic metal thin film 23 (platinum thin film). As shown in FIGS. 1 and 2, the light projecting lens 33 is disposed in the internal space K of the apparatus housing 1. The light projection lens 33 is disposed on the rear plate 12 side of the apparatus housing 1. The light projecting lens 33 faces the catalytic metal thin film 23 (platinum thin film) of the hydrogen gas detection element 2 and is disposed on the ceiling plate 15 side of the apparatus housing 1 with a space from the catalytic metal thin film 23.

  The light emitting element 34 is, for example, a light emitting diode (LED) that emits white light (hereinafter referred to as “light emitting diode 34”). The light emitting diode 34 is electrically connected to the LED drive circuit 35. The LED driving unit 35 is electrically connected to the LED power source 36.

The light-emitting side optical fiber element 37 is a glass fiber or a polyfiber, and is used as an optical fiber cable, for example.
The light emitting side optical fiber element 37 optically connects the light emitting diode 34 and the light projecting lens 33, and transmits the light emission (light) of the light emitting diode 32 to the light projecting lens 33. The light projecting lens 33 irradiates the catalyst metal thin film 23 (platinum thin film) with the light transmitted by the light-emitting side optical fiber element 37. The light-emitting side optical fiber element 37 is inserted in the ceiling plate 15 of the apparatus housing 1, arranged in the internal space K of the apparatus housing 1, and optically connected to the light projecting lens 33. The light-emitting side optical fiber element 37 is drawn out of the apparatus housing 1 and optically connected to the light emitting diode 34 outside the apparatus housing 1.

  The light receiving unit 32 includes a light receiving lens 38, a light receiving element 39, and a light receiving side fiber element 41.

  The light receiving lens 38 condenses the light from the gas chromink metal thin film 22 (tungsten trioxide thin film) and introduces it into the light receiving element 39. As shown in FIGS. 1 and 2, the light receiving lens 38 is disposed in the internal space K of the apparatus housing 1. The light receiving lens 38 is arranged in parallel with the light projecting lens 33 and is disposed on the front plate 11 side of the apparatus housing 1. The light receiving lens 38 faces the catalytic metal thin film 23 (platinum thin film) of the hydrogen gas detection element 2 and is disposed on the ceiling plate 15 side of the apparatus housing 1 with a space from the catalytic metal thin film 23.

The light receiving element 39 is constituted by, for example, a phototransistor (hereinafter referred to as “phototransistor 39”). The phototransistor 39 receives visible light of the three primary colors (red, green, and blue) in the visible light wavelength range (380 nm to 780 nm), and converts the light intensity of the visible light wavelengths of the three primary colors into the color electric signal f1 (photocurrent). Convert and output. The phototransistor 39 is electrically connected to the hydrogen discrimination means 5 through the signal amplifier 40. The signal amplifying unit 40 amplifies the color electric signal f1 and outputs it to the hydrogen discrimination means 5.
Thereby, the phototransistor 39 identifies the color of the gas chromic metal thin film 22 with the light intensity of the visible light wavelength, and converts the light intensity of the identified color into a color electric signal f1.

The light receiving side optical fiber element 41 is a glass fiber or a polyfiber, and is used as an optical fiber cable, for example.
The light receiving side optical fiber element 41 optically connects the photodiode 39 and the light receiving lens 38, and transmits light collected by the light receiving lens 38 to the photodiode 39. The light-receiving-side optical fiber element 41 is inserted in the ceiling plate 15 of the device housing 1, is disposed in the internal space K of the device housing 1, and is optically connected to the light-receiving lens 38. The light-receiving side optical fiber element 41 is pulled out of the apparatus housing 1 and optically connected to the phototransistor 39 outside the apparatus housing 1.

  In the color identification means 3, the light projecting lens 38 and the light receiving lens 38 are accommodated in an apparatus unit container 45 as shown in FIG. The unit container 45 is disposed in the internal space K of the apparatus housing 11 and faces the lenses 33 to 38 against the catalytic metal thin film 23 (platinum thin film).

The hydrogen determination means 5 receives the color electric signal f1 and determines hydrogen leakage based on the change of the color electric signal f1.
As shown in FIG. 1, the hydrogen determination unit 5 includes a control unit 51, a signal storage unit 52, a signal calculation unit 53, a determination signal setting unit 54, a hydrogen leak determination unit 55, and an input unit 56.

The control unit 51 is electrically connected to the phototransistor 39 through the color signal amplification unit 40. The control unit 51 is electrically connected to the signal storage unit 53, the signal calculation unit 53, and the input unit 56.
The control unit 51 is electrically connected to the LED driving unit 35 and outputs a light emission electric signal fd to the LED driving unit 35.

  The signal storage unit 52 stores the reference color electrical signal f2 as data. The reference color electrical signal f2 is a color electrical signal indicating the color (light green) of the gas chromic metal thin film 22 (tungsten trioxide thin film) in an air atmosphere (hydrogen gas non-leakage).

  The signal calculation unit 53 calculates the absolute value (f3 = | f2-f1 |) of the difference electric signal f3 by subtracting the electric color signal f1 from the reference color electric signal f2. The signal calculation unit 53 is electrically connected to the hydrogen leak determination unit 55 and outputs a differential electric signal f3 to the hydrogen leak determination unit 55.

The determination signal setting unit 54 sets a determination electric signal fh indicating the hydrogen gas concentration. For example, the determination signal setting unit 55 includes a variable resistor 54 </ b> A and is electrically connected to the main power supply 57. In the discrimination signal setting unit 54, the discrimination electric signal fh (current) is changed by changing the resistance value of the variable resistor 54A.
The discrimination electric signal fh (current) is set according to the hydrogen gas concentration to be discriminated (detected) with the reference color electric signal f2 (current) being zero.
When increasing the hydrogen gas concentration to be determined, the resistance value of the variable resistance value 54A is decreased to increase the determination electric signal fh (current). Conversely, when the hydrogen gas concentration to be determined is decreased, the variable resistor The resistance value of 54A is increased to decrease the discrimination electric signal fh (current).
The determination signal setting unit 54 </ b> A is electrically connected to the hydrogen leak determination unit 55 and outputs a determination electric signal fh to the hydrogen leak determination unit 55.

The hydrogen leak discriminating unit 55 compares the differential electric signal f3 and the discriminating electric signal fh, and discriminates hydrogen gas leak when the differential electric signal f3 is equal to or greater than the discriminating electric signal fn.
The hydrogen leakage determination unit 55 is electrically connected to the alarm device 6 and outputs an alarm electric signal fk to the alarm device 6.

  The input unit 56 includes a reference color electrical signal setting switch 56 </ b> A and is electrically connected to the control unit 51. The input unit 56 outputs the acquired electrical signal f4 to the control unit 51 based on the operation of the setting switch 56A.

  As shown in FIG. 1, the alarm means 5 (alarm device) inputs an alarm electric signal fk from the hydrogen leakage saddle 55 and issues an alarm. The alarm device 5 is configured by a horn, a bell, an indicator light, or the like, and is electrically connected to the hydrogen leak determination unit 55.

<Monitoring and discrimination (detection) of hydrogen gas leakage>
Next, monitoring and discrimination (detection) of hydrogen gas (H ₂ ) leakage by the optical hydrogen gas detection switch X1 will be described with reference to FIGS.
For convenience of explanation, FIG. 1 shows an air atmosphere in which hydrogen gas (H ₂ ) does not leak into the gas monitoring region Y (hereinafter referred to as “hydrogen gas non-leakage”), and FIG. This is a hydrogen gas atmosphere in which hydrogen gas (H ₂ ) leaks (hereinafter referred to as “hydrogen gas leak”). The gas monitoring area Y is an area where there is a risk of explosion due to hydrogen gas leakage.

In FIG. 1, the optical hydrogen gas detection switch X1 arranges the apparatus housing 11 in a hydrogen gas monitoring region Y such as a process or facility using hydrogen gas (H ₂ ) in a manufacturing factory, for example.
Thereby, the hydrogen gas detecting element 2, the light projecting lens 33, and the light receiving lens 18 are not leaked with hydrogen gas and are exposed to the air atmosphere.

In the optical hydrogen gas detection switch X1, the light emitting diode 34, the phototransistor 39, the signal amplifying unit 40, the LED driving unit 35, the LED power source 36, the hydrogen discriminating means 5, the main power source 57, and the alarm device 6 are set outside the hydrogen gas monitoring region Y. In the non-monitoring area Z. The non-monitoring area Z is an area that is not affected by the hydrogen gas explosion, for example, and is a safe area away from the gas monitoring area Y.
At this time, the light projecting lens 33 is optically connected to the light emitting diode 34 by the light emitting side optical fiber element 37 extending to the hydrogen monitoring region Y and the non-monitoring region Z. The light receiving lens 38 is also optically connected to the light receiving element 39 by the light receiving side optical fiber element 41.

  A person who monitors hydrogen gas leakage (hereinafter referred to as a supervisor) turns on the main power source 57, and further changes (selects) the resistance value of the variable resistor 54A in the discrimination signal setting unit 54 to make the discrimination. The discrimination electric signal fn corresponding to the hydrogen gas concentration to be detected is set.

  Subsequently, the supervisor operates the setting switch 56 </ b> A of the input unit 56. The input unit 56 outputs the acquired electrical signal f4 to the control unit 51 based on the operation of the setting switch 56A.

In the hydrogen determination means 5, the control unit 51 outputs the light emission electrical signal fd to the LED drive unit 35 when the acquired electrical signal f <b> 4 is input. The LED driving unit 35 emits light from the light emitting diode 34.
Light emission (light) of the light emitting diode 34 is transmitted to the light projecting lens 33 by the light emitting side optical fiber element 37. The light projection lens 33 irradiates the catalyst metal thin film 23 (platinum thin film) of the hydrogen gas detection element 2 with the light emitted from the light emitting diode 34 (light).

In the hydrogen gas non-leakage (air atmosphere) of FIG. 1, the hydrogen gas detection element 2 is not exposed to the hydrogen gas (H ₂ ) atmosphere. As a result, the gaschromic metal thin film 22 is not colored, and the tungsten trioxide thin film is not colored (dark blue) but remains light green (before hydrogen atom occlusion).
In the hydrogen gas detection element 2, the gas chromic metal thin film 22 reflects (reflects) light from the catalyst metal thin film 23. The reflected light is collected by the light receiving lens 38 and transmitted to the phototransistor 39 by the light receiving side optical fiber element 41.

Subsequently, the phototransistor 39 receives visible light of the three primary colors, converts the light intensity of the visible light wavelengths of the three primary colors into a color electric signal f1, and outputs it to the signal amplification unit 40. The signal amplifying unit 40 amplifies the color electric signal f1 and outputs it to the hydrogen discrimination means 5 (control unit 51).
When the color electric signal f1 is input, the control unit 51 stores the reference electric signal f2 (data) in the signal storage unit 52.

Subsequently, when hydrogen gas is not leaked, when the color electric signal f1 is further input, the control unit 51 reads out the reference color electric signal f2 from the signal storage unit 52, and the signal calculation unit outputs the color electric signal f1 and the reference color electric signal f2. To 53.
When the color electric signals f1 and f2 are input, the signal calculation unit 53 calculates the absolute value (f3 = | f2−f1 |) of the differential electric signal f3 and outputs the differential electric signal f3 to the hydrogen leakage determination unit 55. Further, the determination signal setting unit 54 outputs the determination electric signal fn to the hydrogen leakage determination unit 55.

The hydrogen leakage determination unit 55 receives the differential electric signal f3 and the determination electric signal fn, and compares the difference electric signal f3 and the determination electric signal fn.
When the hydrogen gas is not leaked, the differential electrical signal f3 is less than the discrimination electrical signal fn (f3 <fn), so the hydrogen leak discrimination unit 55 discriminates that the hydrogen gas is not leaked and outputs the alarm electrical signal fk to the alarm device 6. do not do.

  When hydrogen gas is not leaked, the alarm device 6 does not input an alarm electric signal fk from the hydrogen leak determination unit 55, and therefore does not issue an alarm.

In the hydrogen gas leakage of FIG. 3, the hydrogen gas (H ₂ ) fills the gas monitoring region Y and flows into the internal space K of the apparatus housing 11 from the opening window 17 and the mesh plate 19 (see FIGS. 2 and 3). ).
In the apparatus housing 11, a hydrogen gas detecting element 2 is exposed to a hydrogen gas atmosphere, the catalytic metal film 23 by adsorbing hydrogen gas (H _2), hydrogen gas (H ₂₎ a hydrogen atom (H ^+: Dissociates into protons) and electrons. Hydrogen atoms are diffused from the catalytic metal thin film 23 to the gas chromic metal thin film 23. The gas chromic metal thin film 23 is colored by a reduction reaction (reduction action). For example, a tungsten trioxide thin film changes from chemical formula: WO ₃ (light green) to chemical formula: H _x WO by a reduction reaction (reducing action), and is colored deep blue [see FIG. 3B].
As shown in FIG. 3, the light emission (light) of the light emitting diode 34 is irradiated to the hydrogen gas detection element 2 from the light projecting lens 37, and is reflected by the gas chromic metal thin film 22 to the light receiving lens 38. The reflected light is collected by the light receiving lens 38 and transmitted (introduced) to the phototransistor 37 by the light emitting side optical fiber element 41.

  In the hydrogen gas leakage, as shown in FIG. 3, the phototransistor 39 receives visible light of the three primary colors transmitted to the light-emitting side optical fiber element 41, and converts the light intensity of the visible light wavelengths of the three primary colors into a color electric signal f1. To do. At this time, the color electrical signal f1 is different from the reference color electrical signal f2 (f1 ≠ f2), and has a relationship of, for example, f1> f2. The phototransistor 39 outputs the color electrical signal f1 to the signal amplification unit 40, and the signal amplification unit 40 amplifies the color electrical signal f1 and outputs it to the control unit 51.

  Subsequently, in the hydrogen determination unit 5, the control unit 51 reads the reference color electrical signal f 2 from the signal storage unit 52 and outputs the color electrical signal f 1 and the reference color electrical signal f 2 to the signal calculation unit 53.

When the color electric signals f1 and f2 are input, the signal calculation unit 53 calculates the absolute value of the differential electric signal f3. In hydrogen gas leakage, the relationship between the color electrical signal f1 and the reference color electrical signal f2 is satisfied, and the differential electrical signal f3 does not become zero.
The signal calculation unit 53 outputs the differential electric signal f3 to the hydrogen leakage determination unit 55.

In the hydrogen gas leakage, when the differential electrical signal f3 is input, the hydrogen leakage determination unit 55 compares the differential electrical signal f3 with the differential electrical signal fn.
The hydrogen leak discriminating unit 55 discriminates hydrogen gas leak when the differential electrical signal f3 is equal to or greater than the judgment electrical signal fn (f3 ≧ fn). At this time, the hydrogen gas concentration in the gas monitoring region Y is equal to or higher than the hydrogen gas concentration to be determined.
On the other hand, when the differential electrical signal f3 is less than the discrimination electrical signal fn (f3 <fn), the hydrogen leak discrimination unit 55 determines that hydrogen gas is not leaking. At this time, the hydrogen gas concentration in the gas monitoring region Y is less than the hydrogen gas concentration to be determined.
Subsequently, when it is determined that hydrogen gas leaks, the hydrogen leak determination unit 55 outputs an alarm electric signal fk to the alarm device 6.

  In the hydrogen gas leakage, the alarm device 6 issues an alarm when the alarm electric signal fk is input.

Second Embodiment
The optical hydrogen gas detection switch of the second embodiment will be described with reference to FIG.
In FIG. 4, the same reference numerals as those in FIGS. 1 and 2 denote the same members and the same configuration, and thus detailed description thereof will be omitted.

  In FIG. 4, the optical hydrogen gas detection switch X2 of the second embodiment (hereinafter referred to as “optical hydrogen gas detection switch X2”) has the same configuration as the optical hydrogen gas detection switch X1 of FIGS. The arrangement of the light receiving lens 38 is changed.

In FIG. 4, the light receiving lens 38 is disposed in the internal space K of the apparatus housing 1 so as to face the substrate 22 (transparent substrate). The light receiving lens 38 is optically connected to the phototransistor 39 by the light receiving side optical fiber element 41.
Thus, the light projecting lens 33 and the light receiving lens 38 are arranged with the hydrogen gas detecting element 2 therebetween, the light projecting lens 33 is opposed to the catalytic metal thin film 22 (platinum thin film), and the light receiving lens 38 is the substrate 22 (transparent substrate). ).

  In FIG. 4, the light emission (light) of the light emitting diode 34 is irradiated to the catalytic metal thin film 22 through the light projection lens 33, and passes through the gas chromic metal thin film 22 and the substrate 21 (transparent substrate). The light (transmitted light) transmitted through the substrate 21 is collected by the light receiving lens 38 and transmitted (introduced) to the phototransistor 39 by the light receiving side optical fiber element 41.

  In the optical hydrogen gas detection switch X2, monitoring and discrimination (detection) of hydrogen gas leakage is the same as described with reference to FIGS.

<Third Embodiment>
The optical hydrogen gas detection switch X3 of the third embodiment will be described with reference to FIGS.
5 and FIG. 6, the same reference numerals as those in FIG. 1 and FIG.

  5 and 6, the optical hydrogen gas detection switch X3 (hereinafter referred to as “optical hydrogen gas detection switch X3”) of the third embodiment is the same as the optical hydrogen gas detection switch X1 of FIGS. A configuration is provided, and the arrangement of the color discrimination means 3 and the hydrogen discrimination means 5 is changed.

As shown in FIG. 5, the color identification unit 3 includes a light projecting lens 33, a light receiving lens 38, a light emitting diode 34, and a phototransistor 39 without having the optical fiber elements 37 and 41 in FIG. 1. The light projecting lens 33 and the light emitting diode 34 constitute the light emitting unit 31, and the light receiving lens 38 and the phototransistor 39 constitute the light receiving unit 32.
The light emission (light) of the light emitting diode 34 is directly introduced into the light projecting lens 33, and the reflected light reflected by the gaschromic metal thin film 22 is directly introduced into the phototransistor 39 from the light receiving lens 38.

  The color identification unit 3, the signal amplification unit 40, the LED drive unit 36, the LED power source 37, the main power source 37, and the hydrogen determination unit 5 are accommodated in a unit container 65 as shown in FIGS. The unit container 65 is disposed in the internal space K of the apparatus housing 11. The light projecting lens 33 and the light receiving lens 38 are opposed to the catalytic metal thin film 23 (platinum thin film) of the hydrogen gas detection element 2 with an interval in the internal space K of the apparatus housing 11.

The optical hydrogen gas detection switch X3 arranges the device housing 11 in the gas monitoring region Z, and monitors and discriminates hydrogen gas leakage as described with reference to FIGS.
The optical hydrogen gas detection switch X3 is optimal for the gas monitoring region Y where the risk of hydrogen gas explosion is low, and includes the hydrogen gas detection element 2, the color identification hand 3, and the hydrogen discrimination means 5 all in the device casing 11. Therefore, the optical hydrogen gas detection switch X3 can be downsized. The alarm unit 6 is electrically connected to the hydrogen leakage determination unit 54 (hydrogen determination unit 5) through wiring (not shown) drawn from the inside of the apparatus housing 11 to the outside.

  A hydrogen flame detector installed in a facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to the present invention will be described with reference to FIGS.

  7 to 9, the hydrogen flame detector W includes a hydrogen flame detection means 102, a control means 103, and an alarm means 104.

  The hydrogen detection means 103 includes a gas container 105, an anode 106, and a cathode 107 as shown in FIGS.

  The gas container 105 is formed of, for example, quartz glass and transmits ultraviolet light emitted from the hydrogen flame. The gas container 105 has an internal space S that seals an inert gas (nitrogen, argon, or the like).

  The anode 106 is disposed in an airtight manner in the internal space S of the gas container 105. The anode 106 is composed of a plate electrode 111 (hereinafter also referred to as “anode plate electrode 111”). The anode plate electrode 111 constitutes a positive electrode, and is made of, for example, a rectangular metal plate (length and width: 11.5 cm × 11 cm).

The anode 106 has a plurality of electrode holes 112, 112,..., And each electrode hole 112, 112 opens to the front and back surfaces 111 A, 111 B of the anode flat plate electrode 111. Each of the electrode holes 112, 112,... Penetrates through the anode plate electrode 111 so as to be orthogonal to the front and back surfaces 111 A, 111 B of the anode plate electrode 111.
Each of the electrode holes 112, 112,... Is regularly arranged in a grid as shown in FIG.

  The cathode 107 is disposed in an airtight manner in the internal space S of the gas container 105. The cathode 107 emits photoelectrons to the anode 106 upon incidence (impact / light reception) of ultraviolet light emitted from the hydrogen flame. The cathode 107 is composed of a plate electrode 115 (hereinafter also referred to as “cathode plate electrode 115”). The cathode flat plate electrode 115 constitutes a negative electrode, and is formed of, for example, a rectangular metal flat plate. The cathode flat electrode 115 has the same shape as the anode flat electrode 111.

As shown in FIGS. 7 to 9, the anode 106 and the cathode 107 are arranged in parallel so as to face the entire surfaces 111 </ b> A and 115 </ b> A of the plate electrodes 111 and 115.
As shown in FIGS. 7 and 8A, the anode 106 and the cathode 107 are arranged with a space L between the surfaces 111A and 115A of the plate electrodes 111 and 115, respectively.
As a result, each of the electrode holes 112, 112,... Opens opposite to the cathode flat plate electrode 115 (front surface 115 </ b> A), and is orthogonal to the front and back surfaces 111 </ b> A and 111 </ b> B of the anode flat plate electrode 115 and the front surface 115 </ Be placed.

  In the anode 106 and the cathode 107, the anode plate electrode 111 and the cathode plate electrode 115 are connected by a conductive wire 121. The conductive wire 121 is connected to the anode flat plate electrode 111 in the internal space S of the gas container 105 and extends outside the gas container 105. The conductive wire 121 is connected to the control means 103 outside the gas container 105, extends into the internal space S of the gas container 105, and is connected to the cathode flat plate electrode 151.

  As illustrated in FIG. 7, the control unit 103 includes a voltage application unit 131, a power source 132, a current detection unit 133, and a control unit 134.

The voltage application unit 131 is connected to a power source 132 as shown in FIG. As shown in FIG. 7, the voltage application unit 131 is disposed in the conductive line 121, and is connected to the anode 106 and the cathode 107 (respective plate electrodes 111 and 115) through the conductive line 121.
The voltage application unit 131 applies a pulse voltage between the anode 106 and the cathode 107 (respective plate electrodes 111 and 115) through the conductive wire 121.

The current detection unit 133 is disposed in the conductive wire 121 and is connected to the anode 106 and the cathode 107 (respective plate electrodes 111 and 115) through the conductive wire 121.
The current detection unit 133 detects a current (discharge current) flowing through the conductive wire 121 from the anode 106 to the cathode 107 and outputs a current detection signal if to the control unit 134.

  The control unit 134 is connected to the voltage application unit 131 and outputs a voltage signal vf. The control unit 134 is connected to the current detection unit 133 and detects a hydrogen flame based on the current detection signal if (discharge current). The control unit 134 is connected to the alarm unit 104 and outputs an alarm signal kf.

  As shown in FIG. 7, the alarm means 104 inputs an alarm signal kf from the control unit 134 and issues an alarm. The alarm means 104 is constituted by a horn, a bell, an indicator light, or the like, and is connected to the control unit 134.

  Next, detection of hydrogen flame by the hydrogen flame detector W will be described with reference to FIGS.

  As shown in FIG. 10, the hydrogen flame detector W is disposed, for example, in a hydrogen gas pipe 151 that is piped to a factory or the like. The hydrogen gas pipe line 151 distributes hydrogen gas to a manufacturing process (not shown) using hydrogen gas in a factory.

  In the hydrogen flame detector W, the hydrogen flame detection means 102 (the gas container 105 and the flat plate electrodes 111 and 115) is disposed in the vicinity of the pipe joint 151A (or valve connection position) of the hydrogen gas pipeline 151. The hydrogen flame detection means 102 is arranged at a position where the ultraviolet light emitted from the hydrogen flame is incident on the cathode 106 (cathode plate electrode 115) without being damaged by the hydrogen flame or hydrogen explosion.

  Subsequently, in the control unit 103, the control unit 134 outputs a voltage signal vf to the voltage application unit 131 as illustrated in FIG. 7. The voltage application unit 131 applies an arbitrary pulse voltage between the anode 106 and the cathode 107 (between the plate electrodes 111 and 115) based on the voltage signal vf. The pulse voltage is applied using the anode plate electrode 111 as a positive electrode and the cathode plate electrode 115 as a cathode.

  In the hydrogen flame detector W, the control means 103 and the alarm means 104 are arranged in the monitoring area. The monitoring area is an area that is not affected by hydrogen flame or hydrogen explosion, and is a safe monitoring room or the like separated from the hydrogen gas conduit 151. The control means 103 is connected to the respective plate electrodes 111 and 115 by conductive wires 121.

  When hydrogen gas leaks from the pipe joint 151A or the like of the hydrogen gas pipeline 151 and a hydrogen fire occurs, the hydrogen flame emits ultraviolet light. The ultraviolet light emitted from the hydrogen flame passes through the gas container 105 and enters the cathode 107 as shown in FIG.

The ultraviolet light of the hydrogen flame is directly incident on the front and back surfaces 115A and 115B of the cathode flat plate electrode 115. Further, the ultraviolet light of the hydrogen flame enters the surface 115A of the cathode flat plate electrode 115 through the electrode holes 112, 112,... Of the anode flat plate electrode 111. At this time, the ultraviolet light of the hydrogen flame passes through each of the electrode holes 112, 112,... Without being shielded by the anode plate electrode 111 and enters the surface 115 A of the cathode plate electrode 115.
As a result, the ultraviolet light emitted from the hydrogen flame is incident on the entire front and back surfaces 115A and 115B of the cathode flat plate electrode 115.

  As shown in FIG. 11, the cathode 107 (cathode plate electrode 115) emits photoelectrons to the anode 106 (anode plate electrode 111) by the photoelectric effect when the ultraviolet light emitted from the hydrogen flame is incident. Photoelectrons are emitted from the entire surface 115 A of the cathode flat plate electrode 115 and are attracted to the anode flat plate electrode 111 by the electric field between the anode 106 and the cathode 107. Here, when the control unit 134 controls (selects) the voltage application signal vf to increase the pulse voltage applied between the anode 106 and the cathode 107 and strengthen the electric field, the photoelectrons are sufficiently accelerated, and the gas container 5 Collide with inert gas molecules inside. In collision with the photoelectrons, the inert gas molecules are ionized into electrons and positive ions. Among the electrons and positive ions generated by ionization, the electrons further collide with other inert gas molecules and repeat ionization to reach the entire surface 111A of the anode plate electrode 111.

  On the other hand, the positive ions are accelerated toward the cathode 107, collide with the entire surface 115A of the cathode flat plate electrode 115, and generate many secondary electrons. By repeating this, a large current (hereinafter referred to as “discharge current”) flows from the anode 106 (anode plate electrode 111) to the cathode 107 (cathode plate electrode 115), and a discharge state is established. As described above, the hydrogen flame detection unit 102 causes a discharge current to flow from the anode 106 to the cathode 107 due to a discharge effect between the anode 106 and the cathode 107.

  In the control means 103, as shown in FIG. 7, the current detection unit 133 detects the discharge current flowing through the conductive wire 121 from the cathode 107 (cathode flat plate electrode 115), and the current detection signal if (discharge current) is controlled by the control unit 134. Output to.

Subsequently, the control unit 134 receives the current detection signal if, and when the current detection signal if reaches a certain condition, the control unit 134 determines “hydrogen flame detection” and outputs an alarm signal kf. The condition for determining “hydrogen flame detection” is, for example, “over the current detection signal if and the allowable current value (for example, 50 mA) over step 10, and detect the current detection signal if (discharge current) having the allowable current value. Then, “determination of hydrogen flame is detected” and an alarm signal kf is output ”. The “step number” can be changed from “10” to “5”, and the “allowable current value” can be changed from “50 mA” to “100 mA”, and the number of steps is determined according to the hydrogen flame to be detected (discriminated). And the allowable current value is appropriately selected.
Here, “step” refers to “processing for comparing the current detection signal if and the allowable current value to determine whether or not hydrogen flame is detected (hereinafter referred to as“ hydrogen flame detection processing ”)”. "Step 10" means that the hydrogen flame detection process is repeated 10 times.

The number of steps is set in this way because the influence of ultraviolet light (noise light) other than the ultraviolet light emitted from the hydrogen flame is taken into consideration. Ultraviolet light that becomes noise light is ultraviolet light contained in lightning, etc. By setting the number of steps to “5” or more, ultraviolet light from lightning less than 5 times enters the cathode 106 (cathode plate electrode 115). However, the control unit 134 does not determine (malfunction) as “hydrogen flame detection”.
Note that when not affected by the ultraviolet light that becomes noise light, the control unit 134 sets the “number of steps” to “1” and executes the hydrogen flame detection process once.

  The alarm means 104 issues an alarm when the alarm signal kf is input. Thereby, the person who manages hydrogen gas can recognize the occurrence of a hydrogen fire, can quickly shift to the initial fire fighting activity, and can prevent a secondary disaster.

The hydrogen flame detector W can detect a hydrogen flame by being placed in a facility such as a parking lot where a hydrogen fuel cell vehicle is parked, and is in the vicinity of a storage tank or the like (not shown) for storing liquid hydrogen in a ship, or It is also possible to detect a hydrogen flame by arranging it in the vicinity of a container (not shown) for liquid hydrogen transported by a transport vehicle. Moreover, the hydrogen flame detector W can also be arrange | positioned in the hydrogen gas station which stores hydrogen gas, and can also detect a hydrogen flame. Further, the hydrogen flame detector W can be arranged in a hydrogen fuel cell vehicle or a household hydrogen fuel cell to detect a hydrogen flame.
At this time, the hydrogen flame detection means 102 is disposed at a position where the ultraviolet light emitted from the hydrogen flame can be incident on the cathode flat plate electrode 115 without being damaged by hydrogen explosion or the like.

FIG. 12 shows a parking lot 201 as an example of a facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to the present invention. The parking lot 201 includes a parking space 203 for parking the car 202 and a roof 204. The vehicle 202 is a hydrogen fuel cell vehicle, and the bonnet is equipped with a hydrogen fuel cell 205. An optical hydrogen gas detection switch X is installed on the roof 204. The optical hydrogen gas detection switch X is installed in a hydrogen gas monitoring region Y indicated by a two-dot chain line. The hydrogen gas monitoring region Y is directly under the roof 204 and is a region where hydrogen gas that is lighter than air is likely to stay when hydrogen gas leaks from the hydrogen fuel cell 205, so that hydrogen gas (H ₂ ) leaks. It is suitable as a target for detecting

  Further, a hydrogen flame detector W is erected from the floor 206 in the parking space 203. The hydrogen flame detection device W is installed toward the car 202 parked in the parking space 203, and ultraviolet light from the hydrogen flame F generated from the hydrogen fuel cell 205 installed in the car 202 is transmitted from the light capturing surface 207. Can be captured. Note that the hydrogen flame detection device W may be attached to the wall surface 208 or may be attached to the lower surface of the roof 204.

Furthermore, the parking lot 201 may be a three-dimensional parking lot or a parking lot without a roof. The parking lot 201 may be a public parking lot or a private parking lot. Furthermore, the parking lot 201 may be a temporary parking space for cars at a gas station or a hydrogen gas station. In particular, in a private parking lot, when a home hydrogen fuel cell is installed, leakage of hydrogen gas (H ₂ ) from the home hydrogen fuel cell and generation of hydrogen flame F can be detected. Good.

Moreover, it is preferable that a plurality of optical hydrogen gas detection switches X and hydrogen flame detectors W provided in the parking lot 201 are provided. If a plurality of optical hydrogen gas detection switches X are installed in the hydrogen gas monitoring region Y, it is possible to detect even when hydrogen gas (H ₂ ) leaks over a wide range. If a plurality of hydrogen flame detectors W are installed, the hydrogen flame F can be detected even if the direction of the car 202 parked in the parking space 203 is different.

  The present invention is optimal for monitoring and detecting hydrogen gas leaks and hydrogen flames in parking lots.

X Optical hydrogen gas detection switch W Hydrogen flame detector 2 Hydrogen gas detection element 3 Color identification means 5 Hydrogen discrimination means 21 Substrate 22 Gaschromic metal thin film 23 Catalyst metal thin film 102 Hydrogen flame detection means 103 Control means 104 Alarm means 106 Anode 107 Cathode 111 Anode plate electrode 111A Anode plate electrode surface 111B Anode plate electrode back surface 112 Electrode hole 115 Cathode plate electrode 115A Cathode plate electrode surface 115B Cathode plate electrode back surface 201 Parking space L

Claims (6)

A substrate, a gas chromic metal thin film formed on the surface of the substrate that absorbs and colors hydrogen atoms, and a catalytic metal thin film that is supported on the surface of the gas chromic metal film and that adsorbs hydrogen gas and dissociates into hydrogen atoms. A hydrogen gas sensing element comprising:
A color identifying means for identifying the color of the gaschromic metal thin film, converting the identified color into a color electric signal and outputting;
Hydrogen discrimination means for inputting the color electrical signal and discriminating hydrogen gas leakage based on a change in the color electrical signal;
A facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage, characterized in that an optical hydrogen gas detection switch is provided. The hydrogen discrimination means includes
A signal storage unit for storing a reference color electric signal indicating the color of the gaschromic metal thin film in an air atmosphere;
A signal calculation unit for calculating a difference electric signal by subtracting the reference color electronic signal from the color electric signal;
A discrimination signal setting unit for setting a discrimination electric signal indicating the hydrogen gas concentration;
A hydrogen leakage determination unit that compares the differential electrical signal and the determination electrical signal, and determines that hydrogen gas leaks when the differential electrical signal is greater than or equal to the determination electrical signal;
A facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to claim 1. The color identification means includes
A light emitting element;
A light projecting lens for irradiating the gas chromic metal thin film from the catalytic metal thin film with light emitted from the light emitting element;
A light receiving element that receives visible light of the three primary colors, converts the light intensity of the visible light wavelength of the three primary colors into the color electric signal, and
A light receiving lens that collects light from the gaschromic metal thin film and introduces it into the light receiving element;
A facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to claim 1 or 2. The substrate is a transparent substrate,
The light receiving lens is
A facility such as a parking lot equipped with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to claim 3, wherein light transmitted through the transparent substrate is collected from the gas chromic metal thin film. The color identification means includes
A light-emitting side optical fiber element that transmits light emitted from the light-emitting element to the light projecting lens;
A light-receiving-side fiber element that transmits the condensed light of the light-receiving lens to the light-receiving element;
A facility such as a parking lot provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage according to any one of claims 3 and 4. A gas container that transmits ultraviolet light and seals an inert gas;
An anode disposed in an airtight manner in the gas container;
A cathode disposed in an airtight manner in the gas container and emitting photoelectrons to the anode by the ultraviolet light;
Control means for applying a pulse voltage between the anode and the cathode and detecting the hydrogen flame based on a current flowing from the anode to the cathode;
The anode and the cathode are
It consists of an anode plate electrode and a cathode plate electrode,
The surfaces of the plate electrodes are arranged in parallel with each other, and the surfaces of the plate electrodes are spaced apart from each other.
The anode is
A parking device provided with means for monitoring and discriminating the occurrence of hydrogen gas leakage, comprising a hydrogen flame detector having a plurality of electrode holes that open on the front and back surfaces of the anode plate electrode and penetrate through the anode plate electrode Facilities such as parking lots.

Images