FUSE WITH CAVITY FORMING ENCLOSURE

• US 20070075822A1
• Filed: 10/02/2006
• Published: 04/05/2007
• Est. Priority Date: 10/03/2005
• Status: Abandoned Application

• Current Assignee: Littelfuse Incorporated
• Original Assignee: Littlefuse Incorporated
• Inventors: Pachla, Timothy, Dietsch, Gordon
• Application Number:
  US11/537,906
• Publication Number:
  US 20070075822A1
• Time in Patent Office: Days
• US Class Current: 337/297
• CPC Class Codes: H01H 2085/0412 specially adapted for being mounted on a printed circuit board
• CPC Class Codes: H01H 2085/0414 Surface mounted fuses
• CPC Class Codes: H01H 2085/0555 Input terminal connected to a plurality of output terminals, e.g. multielectrode
• CPC Class Codes: H01H 85/0086 use of a flexible body, e.g. inside the casing
• CPC Class Codes: H01H 85/0411 Miniature fuses
• CPC Class Codes: H01H 85/046 Fuses formed as printed circuits

Abstract

A surface mount fuse includes a substrate, a fuse element applied to the substrate, first and second terminals applied to substrate, first and second conductors connecting the fuse element electrically with the first and second terminals, and an enclosure coupled to the substrate, the enclosure covering the first and second conductors and defining a cavity overlying at least a portion of the fuse element, the cavity allowing for distortion of the fuse element upon its opening.

Claims

1. A surface mount fuse comprising:

a substrate;

a fuse element applied to the substrate;

first and second terminals applied to substrate;

first and second conductors connecting the fuse element electrically with the first and second terminals; and

an enclosure coupled to the substrate, the enclosure covering the first and second conductors and defining a cavity overlying at least a portion of the fuse element, the cavity allowing for distortion of the fuse element upon its opening.

2. The surface mount fuse of claim 1, wherein the substrate is made of a material selected from the groups consisting of:

FR-4, epoxy resin, ceramic, resin coated foil, polytetrafluoroethylene, polyimide, glass and any combination thereof.

3. The surface mount fuse of claim 1, wherein at least one of the fuse elements, first and second terminals, and first and second conductors is made of at least one material selected from the group consisting of:

copper, tin, nickel, silver, gold, alloys thereof and any combination thereof.

4. The surface mount fuse of claim 1, wherein at least one of the fuse element, first and second terminals, and first and second conductors is applied to the substrate via a process selected from the group consisting of:

etching, metalizing, laminating, adhering and any combination thereof.

5. The surface mount fuse of claim 1, wherein the enclosure includes a lid portion having an at least substantially uniform thickness.

6. The surface mount fuse of claim 1, wherein the enclosure includes a sidewall portion extending from the lid portion, the sidewall portion coupled to the substrate.

7. The surface mount fuse of claim 1, wherein the enclosure is coupled to the substrate mechanically, chemically, thermally or via any combination thereof.

8. The surface mount fuse of claim 1, wherein the surface mount fuse includes a deposition of a dissimilar metal on the fuse element at a location desirable for opening.

9. The surface mount fuse of claim 1, wherein the first and second terminals are (i) plated onto the substrate and the enclosure or (ii) plated onto the substrate only.

10. The surface mount fuse of claim 1, wherein the enclosure has at least one characteristic selected from the group consisting of:

(i) being at least substantially rigid;

(ii) having a footprint at least substantially the same as the substrate; and

(iii) being sized to cover multiple fuse elements.

11. The surface mount fuse of claim 1, wherein the cavity is at least partially filled with an arc-quenching material.

12. A surface mount fuse comprising:

a substrate;

a fuse element applied to the substrate;

first and second terminals applied to substrate and first and second conductors connecting the fuse element electrically with the first and second terminals; and

an enclosure coupled to the substrate, the enclosure having a different footprint that the substrate and defining a cavity overlying at least a portion of the fuse element, the cavity allowing for mechanical distortion of the fuse element upon its opening.

13. The surface mount fuse of claim 12, wherein the cavity is at least partially filled with an arc-quenching material.

14. The surface mount fuse of claim 12, wherein the enclosure covers the first and second conductors.

15. The surface mount fuse of claim 12, wherein the first and second conductors are plated onto the substrate only.

16. A surface mount fuse comprising:

a substrate;

a fuse element applied to the substrate;

first and second terminals applied to substrate;

first and second conductors connecting the fuse element electrically with the first and second terminals;

an enclosure coupled to the substrate, the enclosure defining a cavity overlying at least a portion of the fuse element, the cavity (i) allowing for mechanical distortion of the fuse element upon its opening and (ii) at least partially filled with an arc-quenching, mechanically complaint material.

17. The surface mount fuse of claim 16, wherein the enclosure covers the first and second conductors.

18. The surface mount fuse of claim 16, wherein the first and second terminals are (i) plated onto the substrate and the enclosure or (ii) plated onto the substrate only.

19. The surface mount fuse of claim 16, wherein the enclosure has at least one characteristic selected from the group consisting of:

(i) being at least substantially rigid;

(ii) having a footprint at least substantially the same as the substrate; and

(iii) being sized to cover multiple fuse elements.

20. The surface mount fuse of claim 16, wherein the enclosure includes a lid portion having an at least substantially uniform thickness.