JPS63282671A - Thermometric element of temperature abnormality - Google Patents

Abstract

PURPOSE:To obtain a highly reliable thermometric element, by rapidly mixing and contacting an oxidizing agent and a reducing agent with each other by the stirring action caused by the specific gravity difference between the oxidizing agent, the reducing agent and an isolating substance. CONSTITUTION:A receiving vessel 10 composed of a good heat conductor is clamped to the connection part of a large current conductor by a screw. A reactive substance 1 is constituted of an amine type resin monomer (m.p.: 90 deg.C) being a reducing agent 2 and a phthalic anhydride (m.p. 130.8 deg.C) being an oxidizing agent 3 to be respectively hermetically sealed in openable containers 4A, 4B composed of an isolating substance. When the m.p. of the isolating substance is set so as to be higher than the m.p. of each of the oxidizing agent 3 and the reducing agent 2, both of the reducing agent 2 and the oxidizing agent 3 become liquid at the point of time when the temp. of the connection part reaches 130.8 deg.C. When temp. further rises and temp. abnormality reaching the m.p. of the isolating substance is generated, the openable containers 4A, 4B are simultaneously melted, and the reducing agent 2 and the oxidizing agent 3 flow out in a liquid state to be received in the receiving vessel 10 to be mixed and contacted with each other by the substance 4 sedimented by specific gravity difference. By detecting the smoke or gas generated on the basis of this runaway reaction, the abnormality of temp. can be known.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to high voltage distribution panels and gas insulated switchgears.

The present invention relates to a temperature measuring element that is placed at the connection part of a large current conductor of an electrical device housed in a case, such as a gas insulated conduit cable or a gas insulated transformer, and detects temperature abnormality and releases smoke or gas.

[Conventional technology]

SF, gas-insulated transformer TPFR, closed switchboards, etc., which have many conductive contacts such as circuit breaker contacts, switch contacts, disconnector contacts, etc., and conductive connections between conductors, such as SF, gas-insulated transformer TPFR, closed switchboards, etc. The current-carrying function of the current-carrying part is considered important along with the insulation function and switching function, and contact resistance of the conductive contact part increases due to wear and mechanical wear caused by contact arcing due to repeated opening and closing operations, or spreads in the length direction9. It is necessary to monitor temperature abnormalities for increases in contact resistance of conductive connections caused by thermal expansion and contraction of busbars, and to prevent deterioration of current carrying function such as melting of conductors due to temperature abnormalities.

By the way, the deterioration of the current carrying function in these parts occurs due to local concentration of current at the contact surface, and the temperature of the current concentration area is the contact material, 4'QI: softening temperature of the material (usually 400°C or lower) t - It is known that if the current concentration is exceeded, erosion of the current concentration area will progress rapidly. Therefore, in order to predict the deterioration of the current carrying function early, it is necessary to detect it before the current concentration area spreads significantly, or in other words, before the amount of heat generated in the current concentration area increases. It is necessary to place a temperature measuring element as close as possible to the heat generating part to detect local temperature abnormalities. The temperature to be detected is the contact material.

It varies depending on the softening temperature determined by the material of the conductive material and the distance between the heat generating part and the temperature measuring element, so 150
It is desired to be able to select multiple detection temperatures in the temperature range from ℃ to 300'C, and it is desirable to be able to select a detection temperature in multiple stages from ℃ to 300℃, and also to be able to connect each of a large number of conductor connections without impairing the insulation performance of current-carrying parts that are at high potential. It is desirable that the system be able to be set up.

In recent years, gas emission type thermometers have been attracting attention as a thermometer that satisfies these performance requirements. That is, phthalic anhydride (melting point: 1311.8°C) as an oxidizing agent and an amine resin monomer (melting point: 90°C) as a reducing agent are isolated in granular form from polyamide resin (nylon 6.10, melting point: 209°C). By immersing it in a solution at 30°F (°C), pulling it out and drying it, it becomes a granular material with a thin film (isolation layer) on the order of several micrometers formed on the surface, and is made of a good thermal conductor for attaching to a large current conductor. The applicant of the present application has already proposed a container in which a granular oxidizing agent and a reducing agent are mixed and stored in a predetermined ratio at intervals of 1 fli Rd. Therefore, if a conventional temperature measuring element formed in this way is attached to the connection part of a high-current conductor, the isolation layer will melt due to abnormal temperature of the conductor, and the isolation function will be lost. The oxidizing agent and reducing agent, which are already in a liquid state, come into contact with each other and the temperature rises further due to the heat generated due to the intense chemical reaction, resulting in steam of the reactant 1, smoke containing fine particles such as decomposition products, generated gas, etc. Since gas is generated, this smoke or gas can be detected by a smoke detector or gas detector and converted into an electrical signal to generate an alarm signal.

[Problem that the invention seeks to solve]

In the conventional thermometry element formed as described above, polyamide resin (melting point 209°C) and copolymer nylon (melting point 165°C) are used as isolating substances surrounding the oxidizing agent and reducing agent.
), etc., the temperature sensing element is exposed to temperatures of around 100°C, which is the steady-state temperature of a large current conductor, for a long period of time, and the isolating material gradually deteriorates due to heat, resulting in the failure of the diaphragm function. There is a problem with losing the . In particular, at the monitored temperature, the oxidizing agent and reducing agent are already in liquid form.
If the thin film-like isolation layer deteriorates due to heat, the reactants will come into contact at a temperature much lower than the monitoring temperature.
This causes the inconvenience of issuing an erroneous notification signal. Another disadvantage of synthetic resins is that there are restrictions on their melting points (thermal softening temperatures), making it difficult to set arbitrary monitoring temperatures.

An object of the present invention is to provide a temperature measuring element that has high flexibility in setting monitoring temperatures, is provided with an isolation layer that is less susceptible to thermal deterioration, and is therefore highly reliable.

[Means for solving problems]

In order to solve the above problem, according to this researcher, a reactant consisting of an oxidizing agent and a reducing agent, which mix with each other in a molten state to generate smoke or gas, is heated to a predetermined temperature suitable for monitoring temperature abnormalities. They are separated from each other and surrounded by an isolating substance made of a low melting point alloy whose main components are lead and tin, and smoke or gas is generated at the predetermined temperature.

[Effect]

In the means of this invention, the isolating material that isolates the oxidizing agent and the reducing agent from each other is composed of a low melting point alloy mainly composed of lead and tin, such as a solder material or a temperature fuse material, so that the monitoring temperature for temperature abnormalities can be monitored. Several tens of degrees to 600 degrees Celsius
It can be arbitrarily set in multiple stages of about 1D° C. steps in a wide temperature range up to the order of 100 degrees, and the effect of increasing the arbitrariness of monitoring temperature setting can be obtained. In addition, the isolation substance has excellent thermal stability, and it is possible to easily form an unsealable container (capsule) that loses its isolation function by melting at a predetermined temperature, so it has the ability to prevent cross-contamination due to thermal deterioration of the isolation substance. It will be done. Furthermore, there is a large difference in specific gravity between the oxidizing agent and reducing agent and the isolated substance, and when the isolated substance that detects a temperature abnormality melts and settles, an action is created to stir the liquid oxidizing agent and reducing agent, and the oxidizing agent and reducing agent The rapid mixing of the agents promotes the release of gaseous substances.

[Implementation]

The present invention will be explained below based on examples.

FIG. 1 is a schematic diagram showing a temperature measuring element according to an embodiment of the present invention. In the figure, 10 is a receiver made of a good thermal conductor.
It is screwed to a connection part of a large current conductor or the like through the mounting hole 10A. 4 is a cutting container as an isolating substance, and a material whose melting point has a suitable composition for monitoring temperature abnormalities is selected from among low melting point alloy materials such as solder materials and temperature fuse materials whose main components are lead and tin. selected. 1 is a reactant, in this case an amine resin monomer (melting point 90°C) as a reducing agent 2.
) and phthalic anhydride as oxidizing agent 5 (melting point 130.8
°C), and are sealed in demolition containers 4A and 4B, each made of isolation material 4. Cutting container 4A, 4B
Reducing agent to 2. The oxidizing agent 6 is sealed by extruding the reducing agent 2 and the low melting point alloy through double nozzles heated to a predetermined temperature using a double extrusion method to form the thin string-like reducing agent into a tube-like low melting point tube. A reducing agent (or oxidizing agent) is sealed in the cutting container by cutting the alloy tube into a chip shape (like a cored thread solder), crushing both ends, and then melting and sealing it. Chip-like granules 24 and 64 are formed. The granules obtained in this way are in the form of chips of any size with an outer diameter and length of several minutes m or more, and are mixed in the receiver 10 at a ratio suitable for chemical reaction. By storing it, a temperature measuring element is formed.

The melting point of the isolation substance 4 is determined by the oxidizing agent 6. A temperature higher than the melting point of reducing agent 2, in this case the melting point of phthalic anhydride as oxidizing agent 13
If the temperature is set higher than 0.8℃, the cutting container 4 will be removed when the temperature of the connection part of the large current conductor reaches 130.8℃.
Reducing agent 2) Oxidizing agent B in A and 4B both become liquid, but leakage is prevented by the M sealed container and no contact occurs. When a temperature abnormality occurs in which the temperature of the connection further increases and reaches the melting point of the isolating material, the demolition vessels 4A and 4B are simultaneously melted and the liquid reducing agent 2 and oxidizing agent 3 are transferred to the receiver 10.
The liquid reducing agent 2 and oxidizing agent 6 are mixed and brought into contact by the isolating substance 4 which flows out and settles due to the difference in specific gravity, and smoke or gas is generated due to the heat generated due to the runaway reaction. Therefore, by detecting smoke or gas generated by a smoke detector or a gas detector provided in the housing and generating a notification signal, it is possible to detect temperature abnormalities in the large current conductor at an early stage.

There are many combinations of oxidizing agents and reducing agents that cause runaway reactions when they come into contact as liquid reactants 1 that generate smoke or gas when they come into contact, but most importantly, they do not generate harmful smoke or gas. In addition, it is preferable to use a combination of a resin monomer, which becomes a cured resin after the reaction, and a curing agent or a reaction initiator. Combinations of curing agents such as phthalic anhydride and maleic anhydride are preferred.

FIG. 2 is a model diagram showing a temperature measuring element according to a different embodiment of the present invention, showing a granular body 24 consisting of a demolition container 4A and a reducing agent 2 contained therein, and a granular oxidizing agent having no decomposition container. 6 is stored in the receiver 10 at a predetermined mixing ratio, and the cutting volume 64A is
This differs from the previous embodiment in that the receiver is sealed with an isolation membrane 14 made of an isolation material having the same melting point as that of the receiver 10, with the isolation membrane 14 serving as a cutting part. Upon detection, the demolition container 4A loses its isolation function, and as a result, the oxidizing agent 3 and the reducing agent 2 come into contact with each other, and the isolation membrane 1
4, smoke or gas is emitted by drilling. In the temperature measuring element formed in this manner, since the amine resin monomer as the reducing agent 2 having the lowest melting point is sealed by the cutting container 4A, the melting point of phthalic anhydride as the oxidizing agent 6 is 130.8. It is not until the temperature reaches ℃ that the reaction is in a standby state and cross-contact occurs due to the demolition of the demolition container 4A. Furthermore, since the receiver 10 is sealed by the isolation membrane 14, contact between the oxidizing agent 5 and the outside air is prevented, and deterioration or vaporization of the oxidizing agent 2 is suppressed, thereby maintaining the long-term stability of the temperature measuring element. can. Note that which of the oxidizing agent and the reducing agent should be sealed in the cutting container may be determined depending on the ease with which the granular material can be produced.

〔Effect of the invention〕

It is made of a low melting point alloy whose main components are lead and tin, and its melting point is set to a predetermined temperature suitable for monitoring temperature abnormalities. As a result, the limitations on the arbitrariness of the monitoring temperature in conventional thermometers that use synthetic resin films as the isolation material and the uncertainty in the monitoring temperature caused by thermal deterioration of the isolation material are eliminated, and temperature detection on the order of tens of degrees to 300 degrees It is possible to provide a temperature measuring element for detecting temperature abnormalities, which allows monitoring temperature to be arbitrarily set over a wide temperature range, and has high thermal stability and high precision in monitoring temperature abnormalities.

In addition, the oxidizing agent and reducing agent are brought into contact and mixed quickly and reliably due to the stirring action caused by the difference in specific gravity between the oxidizing agent, reducing agent, and isolated substance, which has the advantage of accelerating the chemical reaction and improving smoke and gas generation performance. can get.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a model showing a temperature measuring device according to an embodiment of the present invention;
FIG. 2 is a cross-sectional view of a model showing a temperature measuring element of a different embodiment. 1... Reactant, 2... Reducing agent, 6... Oxidizing agent,
4... Isolation material, 4A, 4B... Demolition container, 10.
... Receiver, 14... Isolation membrane, 2. i, 34... granular material.

Claims (1)

[Claims] 1) A reactant consisting of an oxidizing agent and a reducing agent that generate smoke or gas when mixed with each other in a molten state is mainly composed of lead and tin and has a melting point at a predetermined temperature suitable for monitoring temperature abnormalities. A temperature sensing element for temperature abnormality, characterized in that the elements are isolated from each other and surrounded by an isolating substance made of a low melting point alloy, and generate smoke or gas at the predetermined temperature. 2) The temperature measuring element for detecting temperature abnormalities according to claim 1, wherein the isolation substance is formed as an unsealed container containing an oxidizing agent and a reducing agent, respectively. 3) The temperature measuring element for temperature abnormalities according to claim 1, characterized in that the melting point of the isolating substance is higher than the melting points of the oxidizing agent and the reducing agent.