Reactive fuse element with exothermic reactive material

• US 20070018774A1
• Filed: 07/20/2005
• Published: 01/25/2007
• Est. Priority Date: 07/20/2005
• Status: Abandoned Application

• Current Assignee: Littlefuse Incorporated
• Original Assignee: Littlefuse Incorporated
• Inventors: Whitney, Stephen, Pachla, Timothy, Rodseth, William, Dietsch, Gordon
• Application Number:
  US11/186,130
• Publication Number:
  US 20070018774A1
• Time in Patent Office: Days
• US Class Current: 337/159
• CPC Class Codes: H01H 2085/0414 Surface mounted fuses
• CPC Class Codes: H01H 2085/466 with remote controlled forced fusing
• CPC Class Codes: H01H 2300/036 Application nanoparticles, e.g. nanotubes, integrated in switch components, e.g. contacts, the switch itself being clearly of a different scale, e.g. greater than nanoscale
• CPC Class Codes: H01H 85/0411 Miniature fuses
• CPC Class Codes: H01H 85/046 Fuses formed as printed circuits
• CPC Class Codes: H01H 85/055 Fusible members
• CPC Class Codes: H01H 85/06 characterised by the fusible material H01H85/11 takes precedence
• CPC Class Codes: H01H 85/10 with constriction for localised fusing H01H85/11 takes precedence
• CPC Class Codes: H01H 85/157 Ferrule-end contacts

Abstract

Reactive fuses that contain reactive fuse elements for use in electrical circuits and other applications are provided. In various exemplary embodiments reactive materials and reactive foils are employed to provide a focused, localized heat source which can by used to open or sever a fuse element, or precisely join one or more metallic components. In particular, reactive material can be utilized to open a fuse element in response to the heat generated by a sustained overload current. Alternatively, reactive material may be utilized in the construction of a reactive fuse to join, for example, metallic components to a base fuse element or fuse cap.

Claims

1. A reactive fuse comprising:

a substrate having a top surface, the substrate further including a first end and a second end arranged distal to the first end;

a first conductor positioned adjacent to the first end along the top surface;

a second conductor positioned adjacent to second end along the top surface, the first and second conductors spaced apart along the top surface; and

a reactive material cooperating with the substrate to electrically couple the first and second conductors, the reactive material having a stable state and a exothermic state.

2. The reactive fuse of claim 1, wherein the substrate is an insulative substrate manufactured from the material selected from the group consisting of:

flame retardant woven glass reinforced epoxy laminates, non-woven glass laminates, ceramics, glass, polytetrafluoroethylene, microfiber glass substrates, thermoset plastics, polyimide materials, or any combination of these materials or other suitable materials.

3. The reactive fuse of claim 1, wherein the reactive material is configured to produce a self-propagating exothermic reaction in response to an energy input.

4. The reactive fuse of claim 3, wherein the energy input is selected from the group consisting of:

a current overload, a spark, a flame, a heated filament, focused radio frequency radiation or light amplification by stimulated emission of radiation.

5. The reactive fuse of claim 1, wherein the reactive material is a nano-layered material.

6. The reactive fuse of claim 5, wherein the nano-layed material is constructed of alternating layers of nickel and aluminum.

7. The reactive fuse of claim 1 further comprising a fuse link positioned adjacent to the substrate and the reactive material, wherein the fuse link is electrically coupled to the first and second conductors.

8. The reactive fuse of claim 7, wherein reactive material converts from the stable state to the reactive state in response to an energy input to sever the fuse element.

9. The reactive fuse of claim 8, wherein the energy input is selected from the group consisting of:

a current overload, a spark, a flame, a heated filament, focused radio frequency radiation or light amplification by stimulated emission of radiation.

10. The reactive fuse of claim 1, wherein the reactive material is a reactive foil aligned adjacent to the substrate, and the substrate is a flexible insulative substrate such that the reactive foil and the flexible insulative substrate are bendable to align the first and second conductors in an overlapping arrangement.

11. A fuse element for use in a reactive fuse, the fuse element comprising:

a fuse link; and

a reactive material carried by the fuse link, the reactive material having a plurality of nano-layers configured to produce a self-propagating exothermic reaction in response to an energy input.

12. The fuse element of claim 11, wherein reactive material is constructed of a material selected from the group consisting of a plurality of alternating layers of nickel and aluminum;

titanium and boron;

zirconium and boron;

hafnium and boron;

titanium and carbon;

zirconium and carbon;

hafnium and carbon;

titanium and silicon;

zirconium and silicon;

niobium and silicon;

zirconium and aluminum;

lead and aluminum.

13. The fuse element of claim 11, wherein the fuse link is a cylindrical fuse link.

14. The fuse element of claim 13, wherein the fuse link includes an exterior surface, the exterior surface arranged to carry the reactive material.

15. The fuse element of claim 14, wherein the reactive material spirally engages the exterior surface of the fuse link.

16. The fuse element of claim 11, wherein fuse link includes first and second ends spaced apart by the reactive material to define a fusing area.

17. A method of forming a fuse element comprising:

providing an electrically conductive fuse link having a bonding surface;

aligning a reactive material adjacent to the bonding surface of the fuse link, , the reactive material having a plurality of nanolayers configured to produce a self-propagating exothermic reaction in response to an energy input

establishing a fusing area, the fusing area defined between the reactive material and the fuse link; and

securing the reactive material to bonding surface to define a reactive fuse element.

18. The method of claim 17, wherein the electrically conductive fuse link is a cylindrical fuse link having a hollow interior.

19. The method of claim 18, wherein the reactive material is carried within the hollow interior of the fuse link.

20. The method of claim 17, wherein the fusing area encompasses a first end of the fuse link and a second end of the fuse link, the second end of the fuse link formed distal to the first end.

21. The method of claim 17, wherein the reactive material is secured using a silicone cover affixed adjacent to the bonding surface.

22. The method of claim 17, wherein the reactive material is secured using an adhesive positioned between the fuse link and the reactive material.