JPS5852290B2 - Fuse element and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuse element used for protecting an electrical system.

Traditionally, Ag has been widely used as an element in current-limiting fuses due to its advantages such as its chemical stability, which means that it does not change much over time, and its excellent conductivity, which allows it to be shaped with excellent breaking properties. ing.

However, with conventional current limiting fuses that use Ag as an element and silica sand as an arc extinguisher, even if the fuse element melts, the current is supplied within a unit time in a small current range of several times the rated current or less. Since the energy is not large enough, falgellite, which is a molten vaporized product of the fuse element and arc quenching agent, does not reach a high resistance in a short period of time, resulting in failure to shut off.

In order to improve the breaking performance of a current-limiting fuse in a small current range of several times the rated current or less, the inventors developed a current-limiting fuse using Ag as an element and silica sand as an arc-extinguishing agent.
Instead of the g-element, we first proposed a fuse element in which a fluorine compound with excellent interrupting properties was dispersed in a metal with excellent conductivity such as Ag (Japanese Patent Application No. 51-674).
No. 31).

By using this element, we succeeded in interrupting small current ranges several times the rated current, which conventional current limiting fuses could not do, without impairing the breaking performance in large current ranges.

This invention improves the breaking performance in a small current range of several times the rated current or less, which could not be broken by conventional current limiting fuses that use Ag as an element and silica sand as an arc extinguisher. The purpose is to provide a fuse with breaking performance in a large current range equivalent to
Specifically, a material constituting a partition wall is provided on the inner wall of a highly conductive metal, and a fuse element filled with a material that generates an excellent arc-extinguishing gas when the element fires is used. The inventor succeeded in achieving this goal, and discovered that the material was filled inside the material constituting the internal partition wall of a metal with excellent conductivity, and was used as a material that generates excellent arc-extinguishing gas when the element fires. It was recognized that the breaking performance in the small current range could be improved by using a substance with excellent arc-extinguishing properties other than the fluorine compound proposed by et al.

Metals with excellent conductivity used in the fuse element of this invention include Ag tAl tAu tcci l
Cu+Pb+Sn, Zn, and alloys based on these metals are suitable, and in addition to these, a wide variety of highly conductive metals used in fuses can be used.

In addition, as the material with excellent arc extinguishing properties to be filled into the metal with excellent conductivity, which is suitable for this invention, a single substance or a compound containing CI, S, and Se, which are stable when the fuse is not activated, or the above-mentioned CI, S, It is a single powder containing Se or a mixture of these compound powders and a fluorine compound, and it is a substance that generates a gas containing electrically negative atoms with excellent arc extinguishing properties only when the fuse is activated. Specifically, S, Ag2S, Al2S3. Cu2S
, CaS, FeS.

Ge52, MnS, NiS, pbs SiS
t Sulfur and sulfur compounds such as SnS, ZnS,
Se y Ag2 Se + CdSe, selenium and selenium compounds such as Zn5e, BaCl2 tcc
i4s CuCl2, CoCl2. C2C13F
eC12s MgCl2+ M nc12 t NiC
AIF3jBeF29CaF2 j Fe
F3 t MgF2jMnF2 p ZrF4 , CF
A powder mixture substituted with a fluorine compound such as 2''CF2 t C2C12F4 is used.

In addition to the above-mentioned materials, in the electric circuit, CI, S, which is thermally stable against temperature rise due to fuse load current,
Any single substance or compound containing Se can be used as a substance to be filled into the highly conductive metal of the present invention.

The structure of the fuse element of this invention is shown in Fig. 1a and b.
As shown in the wire element shown in FIG. 2 and the ribbon element shown in FIGS. It is filled with substance 3.

The partition wall 2 is used in electrical systems where the temperature of elements is likely to rise, such as in systems that are frequently opened and closed or that are prone to overload, where the metal 1 with excellent conductivity reacts with the substance 3 with excellent arc extinguishing properties, or This is provided to prevent the phenomenon in which the electrical resistance of the element increases and deteriorates due to corrosion.

Therefore, when a thermally stable material is used as the material with excellent arc-extinguishing properties, or when the temperature rise of the element due to overload current is small, Fig. 1 a, b, Fig. 2 a.

The structure of the fuse element shown in Fig. 3a, b1 is similar to the structure of the fuse element shown in Fig. 4a, b, but the partition wall 2 is omitted.

Materials used for the partition wall 2 provided to prevent direct contact between the highly conductive metal 1 and the highly arc-extinguishing substance include Al2O3, Be02Cao 1 MgO.
Chemically and thermally stable oxides such as y S i02 y Th02 t Z ro 2, or compounds or mixtures containing these oxides as the main component, or containing the above oxides as the main component and trace amounts of other impurity elements. In addition to these, glass powders such as soda glass, lead glass, and silicate glass, as well as highly heat-resistant organic materials such as silicone resin and fluororesin, can be used. Powders of compounds can also be widely used.

A specific method for manufacturing a fuselage membrane having partition walls according to the present invention will be explained.

Powders of refractories, glass, heat-resistant resins, etc. are stirred and mixed with a binder and a solvent such as water or alcohol to create a paste-like partition wall material.

Note that kaolin is used as a binder. Many adhesive resins such as dextrin, polyvinyl alcohol, sodium silicate, and others can be used.

Next, a tube made of a highly conductive metal prepared in advance is immersed in the barrier rib material and then taken out, the barrier rib material adhering to the outer surface of the tube is wiped off, the tube is heated and dried, and if necessary, the barrier rib material is By repeating the application, a partition wall of a predetermined thickness is fixed to the inner wall of the conductive tube.

After that, the conductive tube with partition walls formed on its inner wall is filled with a powder of a material with excellent arc-extinguishing properties without applying vibration, and further processes such as swaging, extrusion, rolling, and annealing are repeated. Fuse elements with appropriate dimensions and shapes can be easily manufactured.

In addition, in the method for manufacturing the fuse element of the present invention described above, if the material with excellent arc-extinguishing properties filled into the conductive metal tube is thermally stable, or if the temperature rise of the fuse is slight. In some cases, the step of applying the barrier rib material can be omitted.

The fuse element of this invention is made by filling the highly conductive metal with a highly arc-extinguishing substance as described above.
A current-limiting fuse is constructed by installing an arc-extinguishing agent such as silica sand inside the fuse cylinder, and when the element fuses and fires, the substance filled in the element with excellent arc-extinguishing properties melts and vaporizes, resulting in arc-extinguishing properties. It generates an excellent gas, and the arc extinguishing is quickly completed by the cooling deionization effect of the gas containing electrically negative atoms or the arc disturbance effect, so the conventional method using M as an element and silica sand as an arc extinguisher is not suitable. It is now possible to interrupt currents in the small current range, several times the rated current, which cannot be interrupted with flow fuses, and moreover, the volume ratio of the arc-extinguishing material filled in the conductive metal can be reduced by processing such as drawing, wire drawing, and rolling. As long as it can be molded as a fuse element, even in a large current range it will exhibit an excellent breaking effect equivalent to a conventional current limiting fuse that uses Ag as an element and silica sand as an arc extinguisher.

Furthermore, by providing a partition wall to prevent contact between the metal with excellent H1 conductivity and the material with excellent arc-extinguishing properties filled in the metal, the fuse element of the present invention can be used in an electrical system. C1, F, filled in the metal for temperature rise when used.
Even in the case of highly corrosive arc-extinguishing substances such as S and Se, the reaction between the arc-extinguishing substance and conductive metal is prevented, so it can withstand repeated overload currents when used as a protective fuse in electrical systems. It also has an excellent lifespan.

Furthermore, the current limiting fuse of this invention installed in the fuse cylinder together with an arc extinguishing agent such as sand
Due to the sealed structure, the shutoff time is extremely short, so toxic gases such as CI, F, S, and Se can be released by the arc extinguisher placed near the fuse element such as silica sand. The fuse element of the present invention can be safely used as a limited fuse element because it is rapidly cooled and does not diffuse into the fuse tube needle that aggregates on the surface of the arc extinguishing agent such as silica sand. It can be widely used as an element.

[Brief explanation of the drawing]

1A and 1B are a side sectional view and a cross sectional view showing an embodiment of the present invention having a partition wall; FIGS. 2A and 2B are a side sectional view and a cross sectional view showing an embodiment of the same; Figure a″J
, - and b are a side sectional view and a cross-sectional view showing an embodiment without a partition wall of the present invention, and Fig. 4 a''J, - and b are a side sectional view and a cross-sectional view showing an embodiment thereof. 1...Metal with excellent conductivity, 2...
Partition wall, 3...A material with excellent arc-extinguishing properties. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A metal hollow cylinder with excellent conductivity, a substance with excellent arc-extinguishing properties filled in the hollow cylinder, and a hollow cylinder that prevents this substance from directly contacting the hollow cylinder. A fuse element characterized by consisting of a partition wall provided inside the fuse element. 2 Ag and AltAu as metals with excellent conductivity. The fuse element according to claim 1, characterized in that Cu, CdpPb, SnsZn, and alloys based on these metals are used. 3 S and S compounds as substances with excellent arc-quenching properties,
The fuse element according to claim 1, characterized in that one or more of Se, Se compounds, and C1 compounds are used. 4 Sb and S compounds, S as substances with excellent arc-quenching properties
The fuse element according to claim 1, characterized in that one or more of e and Se compounds, C1 compounds, and a fluorine compound are used. 5 A1□03. as a substance constituting the partition wall. BeO. CaOp MgO, S io 2 y Th02 s
Claim 1, characterized in that one type or a mixture of two or more types of thermally stable oxides such as ZrO2, or a naturally occurring refractory whose main component is said oxide is used. Fuse element listed. 6. The fuse element according to claim 1, characterized in that one or more types of glass powders such as soda glass, lead glass, and silicate glass are used as materials constituting the partition walls. 7. The fuse element according to claim 1, wherein an organic compound having a high melting point, such as a fluororesin or a silicone resin, is used as the material constituting the partition wall. 8. A material constituting a partition wall is placed in contact with the inner wall of a metal hollow cylinder with excellent conductivity, and then a material with excellent arc-extinguishing properties is filled inside the material constituting the partition wall, and then, A method for manufacturing a fuse element, which comprises a process of forming it into a predetermined shape by subjecting it to a cross-sectional reduction process such as drawing, wire drawing, or rolling.