Lead-free primary side fuse

Abstract

This invention relates to a lead-free primary-side fuse, which mainly includes an insulating body with an internal hollow cavity, two conductive inner caps, at least one conductive fuse element, and two conductive outer caps. The two conductive inner caps are respectively fitted onto both ends of the insulating body. The conductive fuse element is longitudinally inserted into the hollow cavity, with its two clamping ends extending out of the cavity and bent. Lead-free riveting and spot welding are applied to the outer side surface of the corresponding inner cap ends. The two conductive outer caps are respectively fitted onto the outside of the inner caps, with the inner wall surface of the outer cap sidewall and the outer wall surface of the inner cap sidewall in direct contact. The two are connected by lead-free riveting and spot welding. The end face of each outer cap is integrally formed with an outwardly extending conductive terminal. With the above structure, this invention completely eliminates the traditional solder layer to achieve lead-free environmental protection. At the same time, the contact resistance is greatly reduced through tight physical pressing and spot welding, thereby improving the high-current conductivity stability and structural impact resistance.

Claims

1. A primary-side fuse, comprising: A main body, made of insulating material and having a hollow cavity inside; two inner caps, made of conductive material and respectively fitted onto the two ends of the main body from the outside, with the inner sidewalls of the inner caps being spot-welded to the outer sidewalls of the main body without lead; at least one fuse element, made of conductive material and longitudinally inserted into the hollow cavity of the main body, with each fuse element having a clamping end at both ends, the clamping end extending out of the hollow cavity of the main body, and after bending, being spot-welded to the outer side of the corresponding end of the inner cap without lead; two outer caps, made of conductive material and respectively fitted onto the outside of the corresponding inner caps with lead-free spot-welded, the inner wall surface of the sidewall of each outer cap being in a direct fit with the outer wall surface of the sidewall of the corresponding inner cap, and each outer cap having an integrally formed conductive terminal extending outward axially at its end face.

2. The primary fuse as described in claim 1, wherein the number of fuse elements is two.

3. A primary fuse as described in claim 1 or 2, wherein the cavity is filled with an arc-extinguishing material that covers the fuse element within the cavity.

4. A primary fuse as described in claim 1 or 2, wherein the fuse element has a plurality of consecutive necks.

5. A primary fuse as claimed in claim 3, wherein the fuse element has a plurality of consecutive necks.

6. A primary fuse as described in claim 1 or 2, wherein a through hole is formed at each end of the body, each inner cap has a through hole, each through hole is aligned with the corresponding through hole of the body, and the clamping end extends out of the two through holes of the insulating body and the through hole of the inner cap before being bent.

7. The primary fuse as described in claim 3, wherein a through hole is formed at each end of the body, each inner cap has a through hole, each through hole is aligned with the corresponding through hole of the body, and the clamping end extends out of the two through holes of the insulating body and the through hole of the inner cap before being bent.

8. The primary fuse as described in claim 4, wherein a through hole is formed at each end of the body, each inner cap has a through hole, each through hole is aligned with the corresponding through hole of the body, and the clamping end extends out of the two through holes of the insulating body and the through hole of the inner cap before being bent.

9. A primary fuse as claimed in claim 5, wherein a through hole is formed at each end of the body, each inner cap has a through hole, each through hole is aligned with the corresponding through hole of the body, and the clamping end extends out of the two through holes of the insulating body and the through hole of the inner cap before being bent.

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