Protective device

• US 8,675,333 B2
• Filed: 05/14/2013
• Issued: 03/18/2014
• Est. Priority Date: 09/04/2009
• Status: Active Grant

• Current Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Original Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Inventors: Wang, Chung-Hsiung, Chiang, Lang-Yi, Luo, Wen-Shiang, Lin, Hung-Ming, Chen, Kuo-Shu
• Primary Examiner(s): Jackson, Stephen W
• Application Number:
  US13/894,160
• Publication Number:
  US 20130250470A1
• Time in Patent Office: 308 Days
• Field of Search: 361/79, 361/103
• US Class Current: 361/103
• CPC Class Codes: H01H 2085/466 with remote controlled forced fusing
• CPC Class Codes: H01H 69/022 of printed circuit fuses
• CPC Class Codes: H01H 85/0047 Heating means
• CPC Class Codes: H01H 85/0065 Heat reflective or insulating layer on the fusible element
• CPC Class Codes: H01H 85/0411 Miniature fuses
• CPC Class Codes: H01H 85/046 Fuses formed as printed circuits
• CPC Class Codes: H01H 85/048 Fuse resistors
• CPC Class Codes: H01H 85/11 with applied local area of a metal which, on melting, forms a eutectic with the main material of the fusible member, i.e. M-effect devices
• CPC Class Codes: H02H 5/00 Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection using simulators of the apparatus being protected H02H6/00; specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems H02H7/00

Abstract

A protective device including a substrate, a conductive section and a first auxiliary medium is provided. The conductive section is supported by the substrate, wherein the conductive section comprises a metal element electrically connected between first and second electrodes. The metal element serves as a sacrificial structure having a melting point lower than that of the first and second electrodes. The first auxiliary medium is disposed between the metal element and the substrate, wherein the first auxiliary medium has a melting point lower than that of the metal element. The first auxiliary medium facilitates breaking of the metal element upon melting.

Claims

1. A protective device, comprising:

a substrate,

a metal element disposed on the substrate, the metal element extending between and being electrically connected to a first electrode and a second electrode, the metal element serving as a sacrificial structure having a melting point lower than that of the first electrode and the second electrode, at least one of the first electrode and the second electrode having a protrusion protruding toward the other one of the first electrode and the second electrode; and

a first auxiliary medium disposed above the substrate and in direct contact with the metal element, the first auxiliary medium having a melting point lower than that of the metal element, the first auxiliary medium facilitating breaking of the metal element upon melting.

2. The protective device of claim 1, wherein a front side of the first electrode faces a front side of the second electrode, and the protrusion of the at least one of the first electrode and the second electrode is located at one of two lateral ends of the front side of the at least one of the first electrode and the second electrode.

3. The protective device of claim 1, wherein each of the first electrode and the second electrode has a protrusion, a front side of the first electrode faces a front side of the second electrode, the protrusion of the first electrode is located at one of two lateral ends of the front side of the first electrode, and the protrusion of the second electrode is located at one of two lateral ends of the front side of the second electrode.

4. The protective device of claim 3, wherein the protrusion of the first electrode and the protrusion of the second electrode are located on a same side of the metal element.

5. The protective device of claim 4, wherein a distance between the protrusion of the first electrode and the protrusion of the second electrode is a closest distance between the first electrode and the second electrode.

6. The protective device of claim 4, wherein a portion of the first auxiliary medium is located between the protrusion of the first electrode and the protrusion of the second electrode.

7. The protective device of claim 1, wherein each of the first electrode and the second electrode has a protrusion, and the protrusion of the first electrode and the protrusion of the second electrode are located on a same side of the metal element.

8. The protective device of claim 7, wherein a distance between the protrusion of the first electrode and the protrusion of the second electrode is a closest distance between the first electrode and the second electrode.

9. The protective device of claim 7, wherein a portion of the first auxiliary medium is located between the protrusion of the first electrode and the protrusion of the second electrode.

10. The protective device of claim 1, wherein a portion of the first auxiliary medium is located between the protrusion of the at least one of the first electrode and the second electrode and the other one of the first electrode and the second electrode.

11. The protective device of claim 1, further comprising an intermediate support disposed between the first electrode and the second electrode and supporting the metal element thereabove,

wherein the first auxiliary medium is disposed between the intermediate support and the first electrode and between the intermediate support and the second electrode.

12. The protective device of claim 11, wherein a portion of the first auxiliary medium is disposed between the intermediate support and the protrusion of the at least one of the first electrode and the second electrode.

13. The protective device of claim 11, wherein each of the first electrode and the second electrode has a protrusion, a portion of the first auxiliary medium is disposed between the intermediate support and the protrusion of the first electrode, and another portion of the first auxiliary medium is disposed between the intermediate support and the protrusion of the second electrode.

14. The protective device of claim 11, comprising a heat-generating element supported by the substrate, the heat-generating element providing heat to at least the first auxiliary medium.

15. The protective device as in claim 14, wherein the intermediate support is an extension of a third electrode coupled to the heat-generating element.

16. The protective device as in claim 14, wherein the heat-generating element is located below the metal element.