FUSE AND ARC RESISTANT END CAP ASSEMBLY THEREFOR

• US 20120068810A1
• Filed: 09/17/2010
• Published: 03/22/2012
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Cooper Technologies Company (Eaton Corporation PLC.)
• Inventors: Spalding, Keith Allen, Kalra, Varinder Kumar
• Granted Patent: US 8,471,671 B2
• Time in Patent Office: Days
• US Class Current: 337/248
• CPC Class Codes: H01H 2085/388 using special materials
• CPC Class Codes: H01H 85/157 Ferrule-end contacts
• CPC Class Codes: H01H 85/24 Means for preventing insertion of incorrect fuse

Abstract

Overcurrent protection fuses with end cap assemblies amenable to automated manufacturing techniques and providing arc burn through resistance when the fusible element opens therein. The end cap assemblies may include washers having arc resistant compositions and may include single or double end cap constructions. Fuse rejection features may be formed in one of the end caps adjacent and may create empty spaces in the end caps.

Claims

1. An overcurent protection fuse comprising:

a nonconductive fuse body having opposed first and second ends;

at least one fusible element located within the fuse body;

a first conductive end cap coupled to the fuse body at the first end, the first end cap electrically connected to the at least one fusible element; and

a second conductive end cap secured to the first end cap, wherein the second end cap defines a fuse rejection feature.

2. The fuse of claim 1, wherein the first end cap includes a first end wall and a first cylindrical side wall.

3. The fuse of claim 2, wherein the first end wall is flat.

4. The fuse of claim 2, wherein the second end cap includes a second end wall and a second cylindrical side wall, the first and second cylindrical side walls in surface engagement with one another.

5. The fuse of claim 4, wherein the fuse rejection feature is formed in the second end wall of the second end cap.

6. The fuse of claim 5, wherein the fuse rejection feature comprises a projection extending away from the first end wall and creating an interior space between the first end wall and the second end wall.

7. The fuse of claim 6, wherein the interior space is empty.

8. The fuse of claim 4, further comprising a washer extending between the first end wall and the second end wall.

9. The fuse of claim 8, wherein the washer is nonconductive.

10. The fuse of claim 9 wherein the washer comprises an arc extinguishing composition.

11. The fuse of claim 10, wherein the arc extinguishing composition includes melamine.

12. The fuse of claim 8, wherein the fuse rejection feature is formed in the second end wall of the second end cap.

13. The fuse of claim 12, wherein the fuse rejection feature comprises a projection extending away from the first end wall and creating an interior space between the washer and the second end wall.

14. The fuse of claim 13, wherein the interior space is empty.

15. The fuse of claim 1, further comprising at least a third end cap coupled to the fuse body at the second end of the fuse body, the third end cap electrically connected to the at least one fuse element.

16. The fuse of claim 15, wherein the third end cap does not include a fuse rejection feature.

17. The fuse of claim 1, wherein the fuse comprises a cartridge fuse.

18. An overcurent protection fuse comprising:

a nonconductive fuse body having opposed first and second ends;

at least one fusible element located within the fuse body;

a first conductive end cap coupled to the fuse body at the first end, the first end cap electrically connected to the at least one fusible element; and

a second conductive end cap secured to the first end cap;

wherein each of the first and second end caps includes an end wall; and

wherein a nonconductive washer extends between the end wall of the first end cap and the end wall of the second end cap, wherein the washer comprises an arc extinguishing composition.

19. The fuse of claim 18, wherein the second end cap defines a fuse rejection feature.

20. The fuse of claim 19, wherein the end wall of the second cap defines a fuse rejecting protrusion creating a clearance between the washer and the protrusion.

21. The fuse of claim 20, wherein the clearance is empty.

22. The fuse of claim 18, wherein the end wall of the first end cap is flat and the washer is flat, the washer in surface engagement with the end wall of the first end cap.

23. The fuse of claim 18, wherein each of the first and second end caps includes a cylindrical side wall, the cylindrical side walls in surface engagement with one another.

24. An overcurent protection fuse comprising:

a nonconductive fuse body having opposed an end;

at least one fusible element located within the fuse body;

a first conductive end cap coupled to the fuse body at the end, the first conductive end cap electrically connected to the at least one fusible element and including an end wall; and

a nonconductive washer extending parallel to and in surface engagement with the end wall, wherein the washer comprises an arc extinguishing composition.

25. The fuse of claim 24, wherein the arc extinguishing composition includes melamine.

26. The fuse of claim 25, further comprising a second end cap secured to the first end cap.

27. The fuse of claim 26, wherein the second end cap includes a fuse rejection projection.

28. The fuse of claim 27, wherein the projection creates an internal space between the first end cap and the second end cap.

29. The fuse of claim 28, wherein the space is empty.