JPS6030052B2 - electric wire fuse - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric wire fuse that prevents bending due to resin pressure during resin molding of a fuse element, and greatly improves fusing characteristics and shearing characteristics.

When molding the fuse body of a sealed electric wire fuse using resin molding, the resin used for the electric wire fuse is
For explosion-proofing when the heat is cut off, we use resins with strong mechanical strength, such as
Polycarbonate, etc. are used, but these resins have high molding temperatures and high molding pressures, so when molding the fuse body housed in the inner cylinder in a mold, it is necessary to use high-temperature, high-pressure resin. Due to the injection pressure, the plugs or caps on both sides of the fuse body are subjected to strong pressure and are displaced or deformed, which may cause the fuse element to bend.

If the fuse element is bent to a large extent due to such molding pressure, the fusing portion of the fuse element may come into contact with the protective container, causing abnormalities in fusing characteristics or causing inconveniences such as poor appearance.

The present invention was developed to prevent bending of such a fuse element during molding, and to further improve explosion-proof performance when the fuse element is blown.

As shown in Fig. 1, for example, on both sides of the central welded part 1,
A ceramic disc 13 having a terminal through hole 4 in the center is inserted into each of the terminal parts 3 on both sides of the fusing part 1 of a fuse element having a terminal part 3 with a shear cut part 2 formed in a part thereof. After inserting the small ceramic circular tube 9 into the outside of each, the end portion 7 of each terminal portion 3 is positioned outside the tube and inserted into the thick ceramic tube 6, and both ends of the ceramic tube 6 and each Terminals 8 with caps are placed on the ends 7 of both terminals 3 of the terminals 3 and sealed with an inorganic heat insulating material 10 interposed therebetween.
The fuse body, in which the ends 7 of the terminal parts 3 of the fuse element are airtightly connected by crimping, soldering, or both, is inserted into the resin mold 12 or the resin case 12 with the wire connecting terminal parts 11 protruding from both sides. The structure is hermetically sealed.

It is convenient to use transparent glass tubes as the small ceramic tube 9 and the thick ceramic tube 6, since it is convenient to see through from the outside to see if the internal fuse element is blown.

In addition, it is desirable that the terminal through-hole 4 of the ceramic disk 13 has a small clearance with the terminal portion 3 of the fuse element in order to prevent bending of the fuse element. It is preferable that the clearance be small in order to reduce rattling between the two. Furthermore,
The small ceramic circular tube 9 also has the function of fixing the ceramic disk 13 adjacent to the port break section 1, and is interposed between the fusing section 1 and the inorganic heat insulating material 10, but the inorganic heat insulating material 1
If 0 is made of a cushioning material such as ceramic paper, the ceramic disk 13 and the small ceramic circular tube 9 will be closely interposed between the fusing part 1 and the inorganic heat insulating material 10 to prevent backlash. Sticking can be prevented.

Next, instead of inserting the small ceramic circular tube 9, as shown in FIG. Compression burrs 5 can also be provided to place the ceramic disks 13 on both sides of the fusing section 1 to prevent bending of the fuse element.

Next, as shown in FIG. 3, a reinforcing plate 14 made of iron, stainless steel, etc. that is in close contact with the inner bottom of the capped terminal 8 is inserted to form a double bottom, and the inside of the reinforcing plate 14 is If the inorganic heat insulating material 10 is inserted to reinforce the cap part from the inside, when the fuse body is resin molded 12, the injected resin pressure will suppress the dents caused by pressing the cap part of the capped terminal 8 in the mold. However, it is more effective in preventing bending of the fuse element. Next, FIGS. 1 and 3 are illustrations of the case of the resin mold 12, and if the central cylindrical part is made transparent like the ceramic tube,
This is convenient for checking from the outside whether or not the fuse element is blown.

, With the above structure, the welding part 1 can be connected to the terminal parts 3 on both sides by the ceramic disk 13 shown in FIGS. 1 and 2.
Since the fuse element is held in place at the center of the ceramic tube 6, even if the cap portion of the capped terminal 8 is pressed by resin pressure during resin molding, the fuse element is held in place by the ceramic disk 13. It is supported by both sides of the fusing part 1 and does not bend, so that there is no abnormality in the fusing characteristics.

There is no bending in appearance. Furthermore, at the time of crinkling, the welded part 1 of the low-melting alloy is shielded from the crinkle arc of the crinkled part 2 by the ceramic disk 13, so it does not instantaneously gasify, and therefore, it is not heated. There is no increase in gas break pressure.

In addition, arc heat is double-shielded by the inorganic small ceramic circular tube 9 and ceramic tube 6, and the capped terminal is also insulated from the inorganic insulation material.
Each part of the resin mold 12 or the resin case 12 is completely thermally protected from arc heat, and there is no generation of gas due to resin burnout, and the explosion-proof load on the resin mold 12 or the resin case 12 is greatly reduced, making it easy to construct a break-proof structure. At the same time, since there is no burnt carbonization of the inner wall of the resin mold 12 or the resin case 12, and there is no burnt gas adhering to the ceramic tube, etc., the insulation resistance value between both terminals after the burnout is also a good value of 100MQ or more at 500V megger. It shows your results.
Furthermore, even when the ceramic disc 13 is fixed on the terminal part 3 by the compression burrs 5 as shown in FIG. As in the case of the ceramic circular tube 9, the fusing part 1 is placed in the center of the ceramic tube 6 to prevent the fuse element from bending due to the resin pressure during resin molding and to maintain the fusing characteristics.

Furthermore, the ceramic disk 13 shields the insulation arc heat of the shattered part 2 to prevent instantaneous gasification of the fusing part 1, and the thick ceramic tube 6 and inorganic heat insulating material 10 protect the fuse element. Resin mold 12 with heat shielding, or
This prevents the resin case 12 from being burnt out and provides excellent shriveling characteristics similar to those obtained when using the small ceramic circular tube 9.

[Brief explanation of the drawing]

1 and 3 are explanatory diagrams showing a partial cross section of the electric wire fuse of the present invention. FIG. 2 is an explanatory diagram of the caulking portion of the electric wire fuse of the present invention. 1
2 is a fusing part, 2 is a cutting part, 3 is a terminal part, 4 is a terminal through hole in the ceramic disk 13, 5 is a compression burr, 6 is a ceramic tube, 7 is an end of the terminal part 3, 8 is a cap 9 is a small ceramic circular tube, 10 is an inorganic heat insulating material, 11 is a wire connection terminal of the capped terminal 8, 12 is a resin mold or resin case, 13 is a ceramic disk, and 14 is a reinforcing plate. Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. A fuse element having terminal portions partially formed with shear cut portions on both sides of a central fusing portion, and a ceramic material having a terminal through hole at the center in the terminal portions on both sides of the fusing portion. After inserting the circular disks and inserting the small ceramic circular tubes into the outside of each disk, insert each end of the terminal section into the thick ceramic tube with the end of the terminal located outside the tube. A terminal with a cap is placed on each end of the terminal and both ends of the fuse element with an inorganic heat insulating material interposed between them, and the wire connection terminal of the terminal with a cap and the end of the terminal of the fuse element are crimped. Or the fuse body is connected airtightly by soldering or both.
An electric wire fuse characterized in that the electric wire connecting terminal portions are made to protrude on both sides and are hermetically sealed in a resin mold or a resin case. 2. Insert ceramic discs with terminal through-holes in the center into the terminal parts on both sides of the fusing part of a fuse element that has terminal parts partially formed with sheared parts on both sides of the central fusing part. Then, a compression burr is provided on the terminal part at the outer base of the ceramic disc, and after the ceramic disc is fixed in the terminal part, the end of each terminal part is positioned outside the pipe inside a thick ceramic pipe. Insert the capped terminal into both ends of the ceramic tube and both terminals, interpose an inorganic heat insulating material, cap and seal each end, and connect the wire connection terminal of the capped terminal and the terminal of the fuse element. An electric wire fuse comprising a fuse body whose ends are hermetically connected by crimping or soldering, or both, and the electric wire connecting terminal portions of the fuse body are made to protrude on both sides and are hermetically sealed in a resin mold or a resin case. .