Inner cap for high voltage fuse

Patent metadata

Field	Value
Publication number	US-10483071-B2
Application number	US-201815862796-A
Country	US
Kind code	B2
Filing date	Jan 5, 2018
Priority date	Jan 5, 2018
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

Provided herein are protection devices, such as fuses. In some embodiments, a fuse may include a hollow body having first and second ends, each of the first and second ends having an end surface and a side surface extending from the end surface. The fuse may further include a fusible element disposed within a central cavity of the hollow body, the fusible element extending between the first and second ends. The fuse may further include an inner cap formed over at least one of the first and second ends. The inner cap may include a center portion in contact with the fusible element, and a plurality of spring legs extending from the center portion, wherein the plurality of spring legs is in contact with the side surface of the first and/or second ends. The fuse may further include endcaps surrounding the first and second ends.

First claim

I claim:

1. A fuse comprising:
a hollow body including a first end and a second end, each of the first and second ends having an end surface and a side surface extending from the end surface;
a fusible element disposed within a central cavity of the hollow body, the fusible element extending between the first and second ends;
an inner cap formed over at least one of the first and second ends, the inner cap comprising:
a center portion in contact with the fusible element, the center portion comprising a central opening, wherein the fusible element extends through the central opening and along an outer surface of the center portion, and wherein the center portion further comprises a free end extending into the central cavity of the hollow body; and
a plurality of spring legs extending from the center portion, the plurality of spring legs in contact with the at least one of the first and second ends; and

a first endcap surrounding the first end and a second endcap surrounding the second end.

2. The fuse according to claim 1 , wherein one or more of the plurality of spring legs is in physical and electrical contact with at least one of the first endcap and the second endcap.

3. The fuse according to claim 1 , the center portion further comprising:
a surface in contact with an end of the fusible element; and
a contoured lip extending from the surface, the free end extending away from the contoured lip.

4. The fuse according to claim 1 , the center portion comprising at least one standoff feature extending away from the hollow body.

5. The fuse according to claim 4 , the at least one standoff feature in physical contact with at least one of the first endcap and the second endcap.

6. The fuse according to claim 5 , the at least one standoff feature creating a gap between the center portion and at least one of the first endcap and the second endcap.

7. The fuse according to claim 1 , each of the plurality of spring legs comprising:
a first bend in direct physical and electrical contact with at least one of the first endcap and the second endcap; and
a second bend in direct physical contact with the side surface.

8. The fuse according to claim 7 , each of the plurality of spring legs further comprising a free end extending away from the side surface.

9. The fuse according to claim 1 , wherein each of the plurality of spring legs is made from a spring material.

10. A protection device comprising:
a hollow body including a first end and a second end, the first end including a first end surface and a first side surface extending from the first end surface, and the second end including a second end surface and a second side surface extending from the second end surface;
a fusible element disposed within a central cavity of the hollow body, the fusible element extending between the first and second ends;
a first inner cap formed over the first end, and a second inner cap formed over the second end, the first and second inner caps each comprising:
a center portion in contact with the fusible element, the center portion comprising a central opening, wherein the fusible element extends through the central opening and along an outer surface of the center portion, and wherein the center portion further comprises a free end extending into the central cavity of the hollow body; and
a plurality of spring legs extending from the center portion, the plurality of spring legs of the first inner cap in contact with the first side surface, and the plurality of spring legs of the second inner cap in contact with the second side surface; and

a first endcap surrounding the first end and a second endcap surrounding the second end.

11. The protection device according to claim 10 , wherein the plurality of spring legs of the first inner cap is in physical and electrical contact with an interior surface of first endcap, and wherein the plurality of spring legs of the second inner cap is in physical and electrical contact with an interior surface of the second endcap.

12. The protection device according to claim 10 , the center portion further comprising:
a surface in contact with an end of the fusible element; and
a contoured lip extending from the surface,
the free end extending away from the contoured lip.

13. The protection device according to claim 10 , wherein the center portion of the first inner cap comprises a first standoff feature extending towards the first endcap, and wherein the center portion of the second inner cap comprises a second standoff feature extending towards the second endcap.

14. The protection device according to claim 13 , wherein the first standoff feature is in physical and electrical contact with the first endcap, and wherein the second standoff feature is in physical and electrical contact with the second endcap.

15. The protection device according to claim 10 , wherein the plurality of spring legs of the first inner cap comprises:
a first bend in direct physical and electrical contact with the first endcap;
a second bend in direct physical contact with the first side surface; and
a free end extending from the second bend, the free end angled away from the first side surface, and
wherein the plurality of spring legs of the second inner cap comprises:
a first bend in direct physical and electrical contact with the second endcap;
a second bend in direct physical contact with the second side surface; and
a free end extending from the second bend, the free end angled away from the second side surface.

16. A protection device comprising:
a hollow body including a first end and a second end, the first end including a first end surface and a first side surface extending from the first end surface, and the second end including a second end surface and a second side surface extending from the second end surface;
a fusible element disposed within a central cavity of the hollow body, the fusible element extending between the first and second ends;
a first inner cap formed over the first end, and a second inner cap formed over the second end, wherein the fusible element is connected to each of the first and second inner caps, and wherein the first and second inner caps each comprise:
a center portion having a central opening receiving the fusible element, wherein the fusible element extends through the central opening and along an outer surface of the center portion, and wherein the center portion comprises a free end extending into the central cavity of the hollow body; and
a plurality of spring legs extending from the center portion, the plurality of spring legs of the first inner cap in contact with the first side surface, and the plurality of spring legs of the second inner cap in contact with the second side surface; and

a first endcap surrounding the first end and a second endcap surrounding the second end, wherein the plurality of spring legs of the first inner cap are in contact with the first endcap, and wherein the plurality of spring legs of the second inner cap are in contact with the second endcap.

17. The protection device according to claim 16 , the center portion further comprising:
a flattened surface in contact with an end of the fusible element; and
a contoured lip extending from the flattened surface,
wherein the free end extends from the contoured lip, and wherein the free end angles away from the fusible element.

18. The protection device according to claim 16 , wherein the plurality of spring legs of the first inner cap each comprises:
a first bend in direct physical and electrical contact with th

Assignees

• Littelfuse Inc

Inventors

• Lasini Derek

Classifications

• H01H85/042

  General constructions or structure of high voltage fuses, i.e. above 1000 V · CPC title

• H01H85/60

  the intermediate or auxiliary part having contacts at opposite ends for co-operation with the base · CPC title

• H01H85/143 Primary

  Electrical contacts; Fastening fusible members to such contacts · CPC title

• H01H85/157

  Ferrule-end contacts · CPC title

• H01H85/38

  Means for extinguishing or suppressing arc (by powder filling H01H85/18; by mechanical tension applied to fusible member H01H85/36) · CPC title