JP2024014605A - Hydrogen fuse and hydrogen detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the presence of a hydrogen gas in an atmosphere without requiring such a special energy as electricity and cut off the conduction state of electricity.

SOLUTION: The hydrogen fuse includes: an insulation case which is a hollow case; a heat generation unit arranged outside the insulation case, the heat generation unit including a normal-temperature catalyst for catalyst-burning a hydrogen gas at normal temperatures; a pair of lead terminals of which top ends are separately arranged in the insulation case; and a soluble alloy body hung between the lead terminals in the insulation case, the soluble alloy body making the lead terminals conductive with each other and cutting off the conduction between the lead terminals by dissolving by heat generation in the heat generation unit.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a hydrogen fuse that detects hydrogen gas in an atmosphere and interrupts electrical conduction, and a hydrogen detection device equipped with the hydrogen fuse.

From the viewpoint of carbon neutrality, various hydrogen consuming devices are being developed. At the same time, from a safety standpoint, it is also required to detect when hydrogen leaks into the atmosphere. Patent Document 1 discloses a hydrogen gas detection sensor that detects hydrogen gas by thermoelectrically converting heat generated by a catalytic reaction between hydrogen gas and a catalyst and detecting a voltage generated.

Japanese Patent Application Publication No. 2006-201100

In the technique described in Patent Document 1, in order to heat the catalyst to a predetermined temperature, combustible gases other than hydrogen gas are also burned, so it is unclear whether the heat generation is due to the catalytic reaction of hydrogen gas. Furthermore, a power source was required to heat the catalyst.

An object of the present disclosure is to provide a hydrogen fuse and a hydrogen detection device that sense the presence of hydrogen gas in the atmosphere and interrupt electrical continuity without requiring special energy such as electricity. do.

The hydrogen fuse according to the first aspect includes a hollow insulating case, a heat generating part including a normal temperature catalyst that is arranged outside the insulating case and catalytically burns hydrogen gas at room temperature, and a heat generating part arranged at a distance from each other in the insulating case. The pair of lead terminals is bridged between the pair of lead terminals and the pair of lead terminals in the insulating case, and the pair of lead terminals are electrically connected to each other, and the heat generated in the heat generating part melts the pair of lead terminals. and a fusible alloy body that blocks electrical conduction.

In the hydrogen fuse of the first aspect, when hydrogen gas is present in the atmosphere, a heat generating section including a room temperature catalyst that catalytically burns hydrogen gas at room temperature generates heat. This heat generation melts the fusible alloy body spanned between the pair of lead terminals within the insulating case, and electrical conduction between the pair of lead terminals is interrupted. Thereby, the state of electrical conduction via the lead terminal can be interrupted without requiring special energy such as electricity.

The hydrogen fuse of the second aspect has a sealing part that covers the opening of the insulating case and seals the pair of lead terminals and the fusible alloy body in the insulating case.

According to the hydrogen fuse of the second aspect, the pair of lead terminals and the fusible alloy can be protected by sealing them within the insulating case using the sealing portion.

In the hydrogen fuse of the third aspect, the insulating case contains aluminum nitride (a material with high heat conductivity).

According to the third aspect of the hydrogen fuse, since it contains aluminum nitride, which is a material with high heat conductivity, heat is easily transmitted from the heat generating part to the fusible alloy body in the insulating case, and the heat of the fusible alloy body is Responsiveness can be improved.

The hydrogen fuse of the fourth aspect has a heat transfer promoting part that promotes heat conduction from the heat generating part to the fusible alloy body.

According to the hydrogen fuse of the fourth aspect, since the heat transfer promoting portion promotes heat conduction to the fusible alloy body, the thermal responsiveness of the fusible alloy body can be improved.

A hydrogen detection device according to a fifth aspect detects hydrogen gas when the hydrogen fuse according to the first aspect 1 or the second aspect and the pair of lead terminals in the hydrogen fuse are disconnected from each other. It is equipped with a notification section that reports.

In the hydrogen detection device of the fifth aspect, when hydrogen gas is present in the atmosphere, the fusible alloy body melts due to heat generation, and conduction between the pair of lead terminals is interrupted. By interrupting the conduction, the notification unit notifies the detection of hydrogen gas. This makes it possible to know that hydrogen gas is present in the atmosphere without requiring special energy such as electricity.

According to the present disclosure, it is possible to provide a hydrogen fuse and a hydrogen detection device that sense the presence of hydrogen gas in the atmosphere and interrupt electrical continuity without requiring special energy such as electricity. It becomes possible.

(A) is a longitudinal cross-sectional view of the hydrogen fuse according to the first embodiment, and (B) is a cross-sectional view taken along the line AA. FIG. 2 is a longitudinal cross-sectional view of the hydrogen fuse according to the first embodiment in a conduction cutoff state. FIG. 2 is a schematic diagram showing an electric circuit in which a hydrogen fuse is provided. FIG. 7 is a radial cross-sectional view of a hydrogen fuse according to a modification of the first embodiment. (A) is a longitudinal sectional view, and (B) is a partially broken sectional view of the hydrogen fuse according to the second embodiment. FIG. 7 is a longitudinal cross-sectional view of a hydrogen fuse according to a second embodiment in a conduction cutoff state. It is a schematic diagram of the hydrogen detection device concerning a 2nd embodiment, (A) shows a state where a relay switch is off, and (B) shows a state where a relay switch is on.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings. The size of each part and the ratio between each part in each drawing referred to below are schematically expressed, and do not necessarily reflect the actual size of each part and the ratio between each part. Note that the reference numerals commonly assigned in each figure indicate the same object even if there is no particular explanation.

<First embodiment>
As shown in FIGS. 1A and 1B, the hydrogen fuse 10 according to the first embodiment of the present invention includes an insulating case 12, a pair of lead terminals 14A and 14B, a fusible alloy body 16, and a flux. 18, a sealing material 20, and a heat generating section 24.

The insulating case 12 has a cylindrical shape and is hollow inside. The insulating case 12 is made of an electrically insulating material. The insulating case 12 preferably includes a material such as fine ceramics such as aluminum nitride and silicon carbide, which have high heat conductivity.

A pair of lead terminals 14A and 14B are each formed at the tip of the lead wire 14, and are arranged in the insulating case 12 so that their tip surfaces face each other and are separated from each other. The lead wires 14 extending from each lead terminal 14A, 14B are arranged along the cylindrical axis of the insulating case 12 and extend outward from the opening of the insulating case 12.

The fusible alloy body 16 is arranged so as to bridge between the pair of lead terminals 14A, 14B, and makes the pair of lead terminals 14A, 14B electrically conductive. The fusible alloy body 16 can be a fusible alloy body commonly used as a material for thermal fuses, and a material with an appropriate composition is selected so that it melts at a predetermined temperature. Specific materials include alloys of metals such as tin and lead, and the melting temperature can be controlled by the composition ratio of these metals.

The flux 18 is provided so as to cover the entire circumference of the fusible alloy body 16 and the joints between the fusible alloy body 16 and the lead terminals 14A, 14B. The flux 18 is used for the purpose of promoting spheroidization during melting of the fusible alloy body 16, and rosin-based and water-soluble fluxes are generally used.

The sealing material 20 is provided to cover the openings at both ends of the insulating case 12, and seals the pair of lead terminals 14A, 14B, the fusible alloy body 16, and the flux 18 inside the insulating case 12. The sealing material 20 can be made of resin.

The heat generating part 24 is provided on the outside of the insulating case 12 so as to cover the outer peripheral surface thereof, and includes a room temperature catalyst that catalytically burns hydrogen gas at room temperature. The room-temperature catalyst generates heat due to catalytic combustion when hydrogen gas is present in the atmosphere.

Examples of such room-temperature catalysts include catalysts containing 0.2% by mass or more of platinum. Furthermore, the term "normal temperature" as used herein refers to a temperature at which no special heating or cooling is performed, and specifically refers to a temperature in the range of approximately 15 to 30°C. Catalytic combustion at room temperature means that the combustion section is not heated with a heater or the like when the catalyst is brought into contact with the measurement gas.

The normal temperature catalyst is capable of burning hydrogen at normal temperature (room temperature), and for example, a metal oxide supported platinum catalyst such as an alumina supported platinum catalyst (Pt-Al ₂ O ₃ ) can be used. As an example, when 1000 ppm of hydrogen is combusted using a catalyst in which 0.2% by mass of platinum is supported on an alumina carrier (0.2% Pt-Al ₂ O ₃ catalyst), the combustion start temperature is equal to room temperature. (Hiroki Sadamori, “Special Combustion Technology Special Feature: Current Status of Catalytic Combustion Technology, Focusing on Catalytic Combustion Barter”, Journal of Japan Fuel Association, Vol. 58, No. 626, June 1979, pp. 422-423) ).

The heat generating part 24 can be formed by a coating film, and as an example of a forming method, a liquid catalyst made by mixing a powdered catalyst such as an alumina-supported platinum catalyst that burns hydrogen at room temperature and distilled water etc. is coated in an insulating case. An example of this method is to apply it to the surface of No. 12 and dry it.

The hydrogen fuse 10 can be used by being electrically incorporated into an electric circuit 50 including an AC power source 52 and an electric device 54, as shown in FIGS. 3 and 5. The electrical equipment 54 may be a device that consumes hydrogen or a device that is dangerous to use in the presence of hydrogen. When the hydrogen fuse 10 is in a conductive state, power is supplied to the electric circuit 50 and the electric device 54 is operated. On the other hand, when the hydrogen fuse 10 becomes non-conductive, power supply to the electric circuit 50 is stopped.

Next, the operation of the hydrogen fuse 10 of this embodiment will be explained.

When hydrogen gas flows into the atmosphere in which the electric circuit 50 in which the hydrogen fuse 10 and the electrical equipment 54 are installed due to hydrogen gas leakage, etc., the room-temperature catalyst in the heat generating part 24 of the hydrogen fuse 10 burns the hydrogen. , the temperature of the heat generating section 24 increases. When the ambient temperature of the fusible alloy body 16 increases and reaches its melting point, the fusible alloy body 16 melts, condenses around the lead terminals 14A and 14B, and is divided, as shown in FIG. As a result, the hydrogen fuse 10 becomes non-conductive, and power supply to the electrical equipment 54 is stopped.

In this way, the hydrogen fuse 10 of the present embodiment increases the temperature due to the presence of hydrogen gas in the atmosphere without requiring special energy such as electricity, and therefore conducts electricity through the lead terminals 14A and 14B. condition can be blocked.

Furthermore, in the hydrogen fuse 10 of this embodiment, the pair of lead terminals 14A, 14B and the fusible alloy body 16 are sealed in the insulating case 12 by the sealing material 20, so that they can be protected from the environment. can.

Furthermore, in this embodiment, since aluminum nitride, which is a material with high heat conductivity, is included as a constituent material of the insulating case 12, heat is easily transmitted from the heat generating part 24 to the fusible alloy body 16 inside the insulating case 12. , the thermal responsiveness of the fusible alloy body 16 can be improved.

In this embodiment, the outer surface of the insulating case 12 is made flat, but as shown in FIG. The heat generating portion 24A may also be formed in the recessed portion 25 as a coating film. In this way, by providing the recess 25 to form the heat generating part 24, the area of the heat generating parts 24, 24A becomes larger compared to the case where the recess 25 is not provided. The distance to 16 will also become closer. Thereby, the recessed portion 25 functions as a heat conduction portion that promotes heat conduction from the heat generating portions 24 and 24A to the fusible alloy body 16, and the thermal responsiveness of the hydrogen fuse 10 can be improved.

<Second embodiment>
A hydrogen fuse 30 according to a second embodiment of the present invention will be described with reference to the drawings. In this embodiment, detailed explanations of the same parts as in the first embodiment will be omitted.

As shown in FIGS. 5(A) and 5(B), the hydrogen fuse 30 of this embodiment includes an insulating case 32, a pair of lead terminals 34A and 34B, a fusible alloy body 36, a flux 38, and a sealing material 40. , and a heat generating section 44.

The insulating case 32 has a hollow rectangular shape and is open on one side. The insulating case 32 is made of an electrically insulating material as in the first embodiment.

A pair of lead terminals 34A and 34B are formed at the tips of the lead wires 34, inserted through the opening of the insulating case 32 along the inner walls of the insulating case 32 that face each other, and are arranged parallel to each other. The lead wire 34 extends outward from the opening of the insulating case 32.

The fusible alloy body 36 is arranged so as to bridge between the pair of lead terminals 34A, 34B, and makes the pair of lead terminals 34A, 34B electrically conductive. As the material of the fusible alloy body 36, the same material as in the first embodiment can be used.

The flux 38 is provided so as to cover the entire circumference of the fusible alloy body 36 and the joints between the fusible alloy body 36 and the lead terminals 34A, 34B. As the flux 38, the same flux as in the first embodiment can be used.

The sealing material 40 is provided to cover the opening of the insulating case 32 and seals the pair of lead terminals 34A, 34B, the fusible alloy body 36, and the flux 38 inside the insulating case 32. The sealing material 40 can be made of resin as in the first embodiment.

The heat generating portion 44 is formed on the outer surface of the insulating case 32 facing the opening. The heat generating section 44 is formed to include a room temperature catalyst that catalytically burns hydrogen gas at room temperature, as in the first embodiment. The heat generating portion 44 can be formed by a coating film in the same manner as in the first embodiment.

The hydrogen fuse 30 of this embodiment can also be used by being incorporated into an electric circuit, similarly to the hydrogen fuse 10 of the first embodiment. Then, due to the inflow of hydrogen gas into the atmosphere, the room temperature catalyst of the heat generating part 44 burns hydrogen, the temperature of the heat generating part 44 rises, and the fusible alloy body 16 melts, as shown in FIG. , condenses around the lead terminals 34A, 34B and is divided. As a result, the hydrogen fuse 30 becomes non-conductive, and power supply to the electrical equipment is stopped.

In this manner, the hydrogen fuse 30 of the present embodiment can also interrupt electrical conduction due to the presence of hydrogen gas in the atmosphere without requiring special energy such as electricity.

<Third embodiment>
In the first and second embodiments, an example has been described in which the hydrogen fuses 10 and 30 are brought into a non-conductive state, thereby stopping power supply to the electrical equipment 54. However, in this embodiment, the hydrogen fuses 10 and 30 are An example in which it is incorporated into the hydrogen detection device 60 shown in FIGS. 7(A) and 7(B) will be described.

The hydrogen detection device 60 includes an electric circuit 50 in which the hydrogen fuse 10 (or the hydrogen fuse 30) is incorporated, and a notification circuit 66. The notification circuit 66 includes a battery 61 and a notification section 62, and is connected to the electric circuit 50 via a relay switch 64.

The relay switch 64 has a movable part 64A and an electromagnet part 64B, and the movable part 64A is connected to the notification circuit 66. The electromagnet section 64B is connected to the electric circuit 50. When electricity is flowing through the electric circuit 50, the relay switch 64 is turned off because the movable part 64A is attracted to the electromagnet part 64B against the force (see FIG. 7(A)). In addition, when electricity is not flowing through the electric circuit 50, the relay switch 64 is placed in a position where the movable portion 64A is biased to conduct the notification circuit 66, and is turned on (see FIG. 7(B)).

The notification unit 62 uses power supplied from the battery 61 to notify the user of hydrogen leakage. The notification method may be a warning sound, voice, lighting of a warning light, display on a display unit (not shown), transmission of warning information to the vendor, or the like. Here, since power is supplied from the battery 61 only when notifying, the capacity may be small; for example, a button battery is sufficient.

In the hydrogen detection device 60 of this embodiment, when the hydrogen fuse 10 is disconnected due to temperature rise, the power supply to the electromagnet section 64B is stopped, and the movable section 64A is moved to a position where the notification circuit 66 is brought into conduction. , and the relay switch 64 is turned on. Thereby, the notification unit 62 can notify the user of hydrogen leakage.

10, 30 Hydrogen fuse 12, 32 Insulating case 14A, 14B, 34A, 34B Lead terminal 16, 36 Fusible alloy body 20, 40 Sealing material 24, 24A, 44 Heat generating part 25 Recessed part (heat transfer promoting part)
60 Hydrogen detection device 62 Notification unit

Claims (5)

A hollow insulation case,
a heat-generating part that is disposed outside the insulating case and includes a room temperature catalyst that catalytically burns hydrogen gas at room temperature;
a pair of lead terminals spaced apart from each other within the insulating case;
A fusible alloy is bridged between the pair of lead terminals in the insulating case, and connects the pair of lead terminals to each other, and melts due to heat generated in the heat generating part to cut off conduction between the pair of lead terminals. body and
Hydrogen fuse with. a sealing portion that covers the opening of the insulating case and seals the pair of lead terminals and the fusible alloy body within the insulating case;
The hydrogen fuse according to claim 1. The insulating case includes fine ceramics.
The hydrogen fuse according to claim 1. having a heat transfer promoting part that conducts heat from the heat generating part to the fusible alloy body;
The hydrogen fuse according to claim 1. The hydrogen fuse according to any one of claims 1 to 4,
a notification unit that reports detection of hydrogen gas when continuity between the pair of lead terminals in the hydrogen fuse is interrupted;
A hydrogen detection device equipped with