JPS5823163Y2 - Hyuzuno Kouzou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tubular fuse, and more particularly to a tubular fuse having a characteristic end structure of the tubular body.

A typical conventional tubular fuse has a structure in which a fuse-fusible body is stretched diagonally within a tubular body, and caps are fitted at both ends of the tubular body.

In such a fuse structure, the end of the fusible body is bent at the edge of the tube and press-fitted into the fitting gap between the tube and the cap, so it is necessary to match the gap size to the cross-sectional area (diameter) of the fusible body.

However, since the tube material such as glass or ceramic shrinks during cooling and sintering during molding, the dimensions of the tube vary, making it practically impossible to adjust the gap size.

For this reason, a larger gap size is generally used to accommodate a fusible body having a larger cross-sectional area.

However, when doing so, the play in the fitting gap increases for fusible materials with small cross-sectional areas, causing the cap to be tilted (the center axis of the cap is tilted relative to the center axis of the tube) or eccentric (the center axis of the tube is tilted relative to the center axis of the tube). (The central axis of the cap shifts relative to the fuse), and when the fuse is mounted, the contact between the fuse holder and the cap becomes insufficient, resulting in an increase in electrical resistance and, in turn, an increase in heat generation, resulting in unstable fuse performance. become.

Furthermore, the fitting gap may be too large, resulting in poor contact between the fusible body and the cap.

On the other hand, there is also the disadvantage that a fusible body having a diameter larger than the fitting gap cannot be attached, and furthermore, the press-fitted fusible body may be deformed or cut at the edge of the tube body.

The present invention was developed in view of the above-mentioned problems, and it can be installed without deforming or cutting even fusible materials with large cross-sectional areas, eliminates inclination or eccentricity of the cap, and further secures the tube and cap more securely. Moreover, the present invention provides a fuse structure that enables more effective and stable soldering.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the accompanying drawings.

1 and 2 show a fuse structure according to an embodiment of the present invention.

In FIG. 1, radial grooves a are formed at both ends of a tube 1 made of an insulator such as glass or ceramic at symmetrical positions in the longitudinal and radial directions of the tube.

The shape and size of groove a may be selected to engage the fusible body.

Approximately gourd-shaped recesses b and C are formed in the outer peripheral surface of the tube body 1 in communication with each groove a.

The recess C consists of a longitudinal part C and an intermediate enlarged part C,
The depth may be selected to accommodate the soluble material.

As clearly shown in the cross-sectional structure of FIG. 2, the tubular portion of the recess C has approximately the same wall thickness as the other tubular portions.

In other words, the recess C is made by recessing the tube wall inward without substantially changing the thickness of the tube 1.

The fusible body 3 is stretched between a pair of grooves 3 at diagonal positions at both ends of the tube, and both ends thereof are housed in the recesses C through the grooves a.

Solder 4 is filled in the recesses C and fused to the inner circumferential surface of the cap 2 in a manner to be described later.

Next, the soldering process of the fuse will be explained with reference to FIGS. 3A and 3B.

As shown in FIG. 3A, the heating plate 5 is tilted with respect to the horizontal plane.
A cap 2 is placed on top of the cap 2 with the opening facing upward, and a predetermined amount of solder (for example, ring-shaped or disk-shaped solder) 4 is put into the bottom of the cap 2 and melted by heating.

Next, the fusible body 3 is stretched and its both ends are recessed into grooves a, C
One end of the tubular body 1, which is engaged with the pipe body 1, is pushed into the cap 2 from above so that the groove a corresponds to the solder pool.

Due to this pushing, the air inside the pipe body 1 expands due to heat and presses the molten solder 4 at the bottom of the cap.

The compressed molten solder 4 enters the recess C from the groove A and fills there, and at this time, the expanded air and excess solder in the recess C are removed from the tip of the longitudinal part C of the recess. The liquid flows out from the cap 2 (Fig. 3B).

The solder 4 filled in the recess C is fused to the inner circumferential surface of the cap 2 by the next cooling process and solidified, thereby embedding the end of the fusible material.

Thereby, the base 2 and the fusible body 3 are firmly coupled electrically and mechanically.

The above-described soldering is performed in the same manner on the other end of the fuse.

In the fuse structure described above, the fusible body 3 is locked and stored in the groove A and the recess C, so that it is not deformed or cut by being pressed between the end of the tube and the cap, and therefore the cross-sectional area is Even large fusible objects can be attached easily.

In addition, since the end of the fusible body is embedded in the filling solder 4 in the recess C and connected to the cap 2, there is no need to provide an extra gap between the tube body 1 and the cap 2 for the fusible body bone, as described above. The tilting (or eccentricity) of the cap will no longer occur.

In addition, the solder filled in the recess C and fused to the inner circumferential surface of the cap 2 not only electrically connects the cap 2 and the fusible body 3, but also connects the pipe body 1 due to its approximately cylindrical shape. To effectively prevent movement of the cap 2 in the rotational direction and longitudinal direction and mechanically fix the cap 2 firmly to the tube body 1.

That is, the blocking action of the longitudinal solder portion C reliably prevents rotational movement of the cap 2 relative to (the central axis of) the tube 1, and the blocking action of the intermediate enlarged solder portion prevents longitudinal movement of the cap 2 relative to the tube 1. is definitely prevented.

This is an extremely advantageous feature in terms of fuse implementation.

Further, during the soldering process of the fusible material, expanded air and excess solder flow out from the tip of the longitudinal portion C of the recess, so that stable and quantitative soldering is possible.

Furthermore, since the recesses C are formed without substantially changing the thickness of the tube 1, the strength of the tube 1 is not weakened by the recesses C.

In the illustrated embodiment, there are a total of four grooves and recesses a at symmetrical positions in the longitudinal and radial directions of the tube.

Although grooves b and C are provided, this is only for manufacturing reasons to ensure accurate diagonally symmetrical positions at both ends of the tube and to facilitate the formation of grooves and recesses a, l) and c (although grooves and recesses a) , l)
, c has the effect of increasing the mechanical fixing effect of the solder filled there), but what is actually used is a diagonally located pair for stretching the fusible body.

Therefore, it is of course possible to omit the remaining pairs of grooves a, l) and c.

As described above, according to the present invention, it is possible to obtain a fuse structure having a simple structure and having advantages in terms of manufacturing, mounting, and performance of the fuse.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the tube body structure of a fuse according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a fuse according to an embodiment of the present invention, and FIGS. 3A and 3B are the fuses shown in FIG. 2. The soldering process is an enlarged partial sectional view for explaining the soldering process. 1... tube body, 2... cap, 3...
... Fusible body, 4 ... Solder, a ... Radial groove, b, C ... Recess.

Claims (1)

[Scope of utility model registration request] Fuse In a fuse that has an insulating tube body 1 that accommodates a fusible body 3 and a cap 2 that fits into both ends of the tube body 1 in an electrical connection relationship with the fusible body 3, the positions on the diagonal line of both ends of the tube body 1 A radial groove a is formed in the tube body 1, and a substantially gourd-shaped recess C is formed on the outer peripheral surface of the tube body 1 so as to communicate with the groove a, without substantially changing the thickness of the tube body 1. A solution 3 is stretched along the diagonal line within the pipe body 1, and its both ends are engaged with the groove a and the recesses C, and the recesses C are filled with the inner periphery of the cap 2. A fuse characterized in that a base 2 and a fusible body 3 are electrically connected to each other by solder fused to the surface, and movement of the base 2 in the longitudinal direction and rotational direction with respect to the tube body 1 is prevented.