JP6916847B2 - Power fuse - Google Patents

Description

The present invention relates to a protective element of an electric circuit, and particularly to a power fuse of a type that actively heats.

Power fuses are widely applied to electronic products and electrical equipment, and prevent them from being destroyed by a large current exceeding the rating flowing through the electronic products and electrical equipment. The principle of a power fuse is that Joule heat is generated by electrical resistance and blows to open the circuit. That is, when a current flows through a conductive power fuse having an appropriate impedance, heat is generated when a current exceeding the rating flows, the fuse is blown by overheating, the circuit opens, and the current flows into electronic products and electrical equipment. prevent. The higher the impedance after fusing, the greater the effect of opening the circuit. Generally, the larger the cross-sectional area of the power fuse, the lower the impedance and the higher the rated current value. When the power fuse and the circuit to be protected are connected in series and used within the rated current value, the smaller the voltage drop and the temperature rise, the better. The power fuse is heated by the flow of a large current exceeding the rating, and an arc discharge occurs before it is completely blown. It is instantaneous, locally high energy, and has strong destructive power. This is an important factor that must be taken into consideration when creating the layout of the power fuse.

Further, if the welding points at both ends of the power fuse are close to each other, even if the power fuse is blown, an arc discharge effect is generated at the welding points at both ends and the effect of protecting the circuit is lost. This point is also a hair store of conventional power fuses.

An object of the present invention is to provide a power fuse that prevents an arc discharge from occurring when the fuse element is blown.

The power fuse according to the present invention includes a tubular body, a fusing unit, and a plurality of second cap bodies, and a first cap body having through holes formed at both ends of the tubular body is provided. Provide each. The fusing unit includes a first fuse element provided in the tubular body and having both ends passing through the through hole of the first cap body and extending outward. The plurality of second cap bodies are provided with a concave portion on one surface and a conducting wire on the other surface, and the concave portion abuts on the outside of the first cap body. Further, both ends of the first fuse element are located between the first cap body and the second cap body to extend the distance between both ends of the first fuse element. Therefore, it is possible to prevent an arc discharge from occurring after the first fusing unit is fusing.

It is a perspective view which showed the power fuse by 1st Embodiment of this invention. It is explanatory drawing which showed the cross-sectional structure of the power fuse disclosed in FIG. It is explanatory drawing which showed the cross-sectional structure of the power fuse by 2nd Embodiment of this invention. It is explanatory drawing which showed the cross-sectional structure of the power fuse by 3rd Embodiment of this invention. It is a perspective view which showed the power fuse by 4th Embodiment of this invention.

In order to explain the content and effect of the present invention, specific examples will be given and detailed with reference to the drawings. FIG. 1 is a power fuse according to the first embodiment, which includes a tubular body 10, a fusing unit 20, and a plurality of second cap bodies 30. Each member is as described below.

The tubular body 10 is provided with first cap bodies 11 at both ends, and through holes 111 are bored in each of the first cap bodies 11. The tubular body 10 is a hollow cylindrical body, but it may be a hollow rectangular parallelepiped.

As disclosed in FIGS. 1 and 2, the fusing unit 20 includes a first fuse element 21 provided in the tubular body 10, and both ends of the first fuse element 21 pass through the respective through holes 111. And stretch outward.

The second cap body 30 is provided with a concave portion 31 on one surface thereof, and is provided with a conducting wire 32 on the other surface. However, if necessary, the second cap body 30 without the conducting wire 32 may be used.

The concave portion 31 of each of the second cap bodies 30 is in contact with the outside of the first cap body 11, and both ends of the first fuse element 21 are located between the first cap body 11 and the second cap body 30. The distance between both ends of the first fuse element 21 is extended.

The first cap body 11, the fusing unit 20, and the second cap body 30 are welded and connected. The welding point is located between the first cap body 11 and the second cap body 30 on the outside of the tubular body 10. Therefore, it is referred to as "external welding". With such a configuration, the distance between both ends of the first fuse element 21 is extended, and when the first fuse element 21 is blown, an arc discharge is generated and the circuit cannot be completely opened, which is effectively prevented. Can be done.

FIG. 3 discloses a second embodiment. In the second embodiment, some members or structures are the same as those in the first embodiment. Therefore, it should be mentioned in advance that the same part will not be described in detail.

In the second embodiment, the fuse element 20 includes a first fuse element 21 and a second fuse element 22 connected to the first fuse element 21. The first fuse element 21 has a melting point shorter than that of the second fuse element 22, and the first fuse element 21 and the second fuse element 22 are provided in the tubular body 10. Further, one end of each of the first fuse element 21 and the second fuse element 22 passes through the through hole 111 and extends outward.

Another feature of the present invention is to achieve the purpose of protection by combining the first fuse element 21 and the second fuse element 22 having different melting points, if necessary.

Further, as disclosed in FIG. 4, a third fuse element 23 may be provided between the first fuse element 21 and the second fuse element 22. In this case, the melting point of the second fuse element 22 is lower than that of the third fuse element 23. Further, the first fuse element 21, the second fuse element 22, and the third fuse element 23 may be linear, spring-shaped, or plate-shaped fuse elements.

FIG. 5 is a perspective view of a power fuse according to a fourth embodiment of the present invention. In the fourth embodiment, the power fuse is changed to a rectangular parallelepiped instead of a columnar shape, and the second cap body 30 is not provided with the conducting wire 32. Made suitable for application to circuits with other specifications.

10 Cylindrical body 11 1st cap body 111 Through hole 20 Fusing unit 21 1st fuse element 22 2nd fuse element 23 3rd fuse element 30 2nd cap body 31 Concave part 32 Conductor

Claims (5)

A tubular body provided with a first cap body having through holes at both ends, and
A fusing unit provided in the tubular body and including a first fuse element having both ends passing through the through hole of the first cap body and extending outward.
It includes a plurality of second cap bodies having a concave portion on one surface and a conducting wire on the other surface, and the concave portion abutting on the outside of the first cap body.
Both ends of the first fuse element are located between the first cap body and the second cap body to extend the distance between both ends of the first fuse element .
The first cap body, both ends of the first fuse element, and the second cap body are welded and connected.
A power fuse characterized by that. In the power fuse according to claim 1,
The tubular body is a hollow cylinder or a hollow rectangular parallelepiped.
Power fuse, characterized in that. A tubular body provided with a first cap body having through holes at both ends, and
A first fuse element provided in the tubular body and one end extending outward through the through hole, and one end provided in the tubular body and connected to the first fuse element. A fusing unit that includes a second fuse element that passes through the through hole and extends outward, and whose melting point of the first fuse element is lower than that of the second fuse element.
It includes a plurality of second cap bodies having a concave portion on one surface and a conducting wire on the other surface, and the concave portion abutting on the outside of the first cap body.
One end of the first fuse element and the second fuse element is located between the first cap body and the second cap body .
A third fuse element is provided between the first fuse element and the second fuse element, and the melting point of the second fuse element is lower than that of the third fuse element.
A power fuse characterized by that. A tubular body provided with a first cap body having through holes at both ends, and
A first fuse element provided in the tubular body and one end extending outward through the through hole, and one end provided in the tubular body and connected to the first fuse element. A fusing unit that includes a second fuse element that passes through the through hole and extends outward, and whose melting point of the first fuse element is lower than that of the second fuse element.
It includes a plurality of second cap bodies having a concave portion on one surface and a conducting wire on the other surface, and the concave portion abutting on the outside of the first cap body.
One end of the first fuse element and the second fuse element is located between the first cap body and the second cap body.
The first cap body, the fusing unit, and the second cap body are welded and connected.
Power fuse, characterized in that. In the power fuse according to claim 3 or 4.
The tubular body is a hollow cylinder or a hollow rectangular parallelepiped.
Power fuse, characterized in that.

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