THERMAL FUSE

• US 20100109833A1
• Filed: 02/01/2008
• Published: 05/06/2010
• Est. Priority Date: 03/26/2007
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Mueller, Michael, Mohr, Thomas, Knab, Norbert, Schulze-Icking-Konert, Georg, Haberl, Nikolas, Kotthaus, Stefan, Stampfer, Stefan
• Granted Patent: US 8,633,795 B2
• Time in Patent Office: Days
• US Class Current: 337/413
• CPC Class Codes: H01H 2037/763 the spring being a blade spring
• CPC Class Codes: H01H 37/761 with a fusible element forming part of the switched circuit H01H37/767 takes precedence
• CPC Class Codes: H05K 1/0293 Individual printed conductors which are adapted for modification, e.g. fusable or breakable conductors, printed switches
• CPC Class Codes: H05K 2201/10181 Fuse
• CPC Class Codes: H05K 3/202 using self-supporting metal foil pattern
• CPC Class Codes: Y10T 29/49107 Fuse making

Abstract

The invention relates to a thermal fuse in a circuit structure, particularly a punched grid, having a plurality of circuit areas, having the circuit structure with connections sited (9) and having a fusible element (3), which is electrically and mechanically connected to the connection sites (9) of the circuit structure, the material of the fusible element (3) having a melting point, in order to melt at an ambient temperature greater than the melting point, such that material of the fusible element (3) collects at the connection sites (9) and the electrical connection formed by the fusible element (3) breaks.

Claims

1-13. -13. (canceled)

14. A thermal fuse in a circuit structure with several circuit areas with connections sites and a fusible element that is electrically and mechanically connected to the connection sites of the soldering flux core circuit structure, wherein the material of the fusible element provides a melting point at an ambient temperature higher than a melting temperature so that material of the fusible material accumulates at the connections sites due to a surface tension and breaks the electrical connection that is created by the fusible element.

15. The thermal fuse of claim 14, wherein the connection sites are separated at a distance from each other at which the melted material of the fusible element are electrically separated from each other at the connection sites.

16. The thermal fuse of claim 14, wherein the fusible element is one of:

soldered;

welded; and

glued to the connection sites.

17. The thermal fuse of claim 14, wherein at least one of:

the fusible element is covered with a soldering flux; and

a soldering flux core is provided in the material of the fusible element or an interlayer between two layers of the material of the fusible element.

18. The thermal fuse of claim 14, wherein the connection sites are arranged at corresponding contact bridges of the circuit structure, and wherein at least one of:

the contact bridges comprise a spring element; and

at least one of the contact bridges comprise a bend with respect to a direction defined by the connection sites.

19. The thermal fuse of claim 14, wherein the circuit structure comprises at least one idle power section that does not contribute to current supply, and at least one cross-section that span transversely to a connection direction defined by the connection sites and that are connected with one of the at least one idle power section and a circuit section.

20. The thermal fuse of claim 19, wherein the fusible element comprises at least one of:

a rectangular shape;

a U-formed section; and

a S-formed section.

21. The thermal fuse of claim 14, wherein the fusible element comprises a deformable material, wherein a deformation force for deforming the fusible element is less than a minimum force that causes a degradation of the fusible element and connection site connections.

22. The thermal fuse of claim 14, wherein the connection sites are arranged on contact elements that each provide a conductive contact capsule and a connection line that is connected to it;

and wherein ends of the fusible element are inserted into the contact capsules and there electrically connected with the aid of a contact material with the contact capsule.

23. A thermal fuse in a circuit structure with a contact element that has a conductive contact capsule and a connection line that is connected to it and with a fusible element in that a soldering flux is embedded, wherein an end of the fusible element is inserted into the contact capsule and there electrically connected with the contact capsule with the aid of a contact material.

24. The thermal fuse of claim 23, wherein the soldering flux is provided as soldering flux core in the material of the fusible element or as interlayer between two layers of the material of the fusible element.

25. The thermal fuse of claim 23, wherein whereby the contact material is a soldering material that has a melting temperature less than or equal to the material of the fusible element.

26. A method for producing a thermal fuse, the method comprising:

melting a contact material in a contact capsule of a contact element by a heat source;

removing the heat source; and

inserting a fusible element into the contact capsule one of simultaneously with and after removing the heat source, wherein the fusible element is partially melted and connects with the contact capsule over the contact material.