JPS58158829A - Fuse - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuse, and relates to a fuse in which a plurality of fuses are stacked on top of each other.

For example, as shown in FIG. , and the remaining part is equipped with a fuse connector 3 and an arc hose/4. Further, a magnetic iron plate 5 for blowing out the arc is provided on the surface of the insulating frame 10 at a position substantially corresponding to the arc horn 4. and by the fuse connectors 3 arranged at the symmetrical positions),
It is stretched between fuse 6t and fuse fixing base 2.2.

Main fusible vessels such as Joki Densei generally have a rated current of 500
It's a trap with ~800 people. For this reason, the fuse 6 is also made of copper as it is relatively small and adapts to the above rated current and can melt in the event of overcurrent. As shown in Figs. 82 to 4, the fuse 6 is constructed by stacking three pieces of fuse 6F to 6CIH made of thin steel plates of 0.25 cm, for example, to make the fuse 6 flexible. It is normal to let it stand.

However, although the fuse 6 having a laminated structure satisfies the requirements for a fuse, it has the problem of large variations in fusing characteristics and has the drawback of lacking reliability.

The present invention has been made in view of the above points, and a seventh object thereof is to provide a fuse having excellent GIII properties with less variation in fusing characteristics.

The present inventor discovered that a fuse made of copper material has a high melting point (108
3C) It is possible to make a large capacity fuse with a small cross-sectional area, but on the other hand, because the melting point is high, even if the cross-sectional area is the same, the instant fusing characteristics can vary widely if the surrounding conditions, especially the heat dissipation state, change. did.

Therefore, the fuse 6 with fuse pieces 61 to 6c11 laminated
0 Near the melting point? Upon inspection, it was found that there were two types: one with no gap between the laminated layers (Figure 3) and the other with a gap G (Figure 4), and it was found that these had significantly different fusing characteristics. .

It was also found that there were more fuses 6 with a gap G, and it was also confirmed that this gap G was enlarged each time the fuse 6 was attached or detached during maintenance and inspection.9.

Therefore, in order to make the heat dissipation state t almost the same regardless of the presence or absence of a gap, the present invention ii.
1. It is covered with a metal whose melting point is lower than that of the fuse.

An embodiment of the present invention will be described below with reference to Figures 5 to 7.

The structure of the fuse 6 is, for example, fuse pieces 6a to 6c'l made of thin copper plates are stacked horizontally, and the fuse pieces 6a to 6c'l are stacked horizontally, and have a very narrow throughput of KJ+3.
It's what I'm looking forward to. The width of this fuse 6 is narrower than the width at both ends, and the middle part is narrower than the width at both ends. be. In the case where there is no gap between the laminated fuse pieces 61 to 6C (Fig. 6), the coating layer of solder 7 is formed only around the periphery, and in the case where there is a gap G (Fig. 7), the gap Gt is Solder 7 is intruding.

Since the overlying layer of the solder 7 is formed as described above, the heat dissipation state of the fuse pieces 6a to 6C within this covering layer can be made almost constant regardless of the presence or absence of Ichinoseki Gv.

When the fuse 6 thus obtained and the conventional fuse (FIG. 2) were tested for fusing characteristics, it was found that the fuse 6 according to the present invention had very little variation and good results were obtained.

Ten fuses were made according to Table 1, and the I and ■υ tests shown in Table 1 were conducted with one without a gap of 7 and one with a forced gap of 7't%. As a result, as mentioned above, although all the conditions for fuse were satisfied,
There was a big difference in the GO test. In other words, in the past, when 200% of the rated current was applied, it could melt down to 40.8 IVIk from the beginning of 11-20 seconds, or after 1 minute and 30 seconds at a slow t, and there were variations within the range of 50 seconds. there were. On the other hand, in the present invention, υ was blown out after 35 seconds at the earliest after 20 seconds from the start of energization (412), and the range of variation was within 15 seconds.

As described above, the embodiments of the present invention can provide a reliable fuse with less variation in fusing characteristics, and since the intermediate portion is soldered with solder 7, the fuse pieces 6a~ 6c is a special song hand R'ktlj
Even if there is no difference, there will be no variation, and handling will be easier.

In addition, fuses made of copper plates are used for long-term use, such as during energization.
PrH conversion progresses due to heat. If this oxidation is carried out at the fi break point, the life of the fuse will be shorter than fiA6, and the fusing characteristics will vary as shown in V above.
This is a solder layer formed by crushing the stacked fuse 6v at both ends of the fuse.This is done to prevent the stacked fuse pieces 6a to 6c from being damaged and to facilitate connection to the fuse fixing base. be.

Incidentally, although the above embodiment has been described with respect to a fuse having a narrow width at the middle portion as shown in FIG. 5, it goes without saying that the present invention can also be applied to a fuse having the same overall width. Further, although a thin copper plate is used as the fuse piece, it is not limited to copper as long as it can be made of an equivalent material. Furthermore, the reason for covering the V with a metal having a lower melting point than the fuse is from a construction point of view, since the fuse of the p1 laminated structure can be easily covered without any gaps.

The solder is not limited to this low melting point gold solder, and it is also possible to use lead or the like.

As explained above, according to the present invention, the heat dissipation conditions at the melting points of the fuses in the laminated structure are made almost the same, so it is possible to provide a highly reliable V-Nishiichi fuse with less variation in the melting characteristics. .

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing the main fuser, Fig. 2 is a perspective view showing a general laminated structure fuse, Figs. 3 and 4 are enlarged views in the E direction of Fig. 2, respectively. FIG. 5 is a horizontal view of a fuse according to the present invention, FIG. 6 and FIG.
This is an enlarged cross-sectional view taken along A-Aill in the figure. 6...Fuse, 6a-6C...Fuse piece, 7.
・・・Semi-first solid Figure 3 Figure 4 θ

Claims (1)

[Claims] 1. In a fuse constructed by stacking a plurality of fuse pieces of the same shape, the entire circumference of the fuse, which is the melting point, is
A fuse characterized by being covered with a metal having a melting point lower than that of the fuse. 2. Claim 1, item 11e, h, wherein the fuse has an intermediate portion narrower in width than both ends, and the narrow intermediate portion is covered with the metal. .