Method for manufacture of a fuse for a printed circuit board

• US 8,705,249 B2
• Filed: 09/01/2010
• Issued: 04/22/2014
• Est. Priority Date: 09/03/2009
• Status: Active Grant

• Current Assignee: Borgwarner BERU Systems GmbH (BorgWarner Incorporated)
• Original Assignee: Borgwarner BERU Systems GmbH (BorgWarner Incorporated)
• Inventors: Luppold, Michael, Dauth, Alexander
• Primary Examiner(s): Dinh, Tuan T
• Application Number:
  US12/873,616
• Publication Number:
  US 20110051388A1
• Time in Patent Office: 1,329 Days
• Field of Search: 361/767, 361770-772, 174260-264
• US Class Current: 361/776
• CPC Class Codes: H01H 2085/0275 Structural association with a printed circuit board
• CPC Class Codes: H01H 2085/0283 Structural association with a semiconductor device
• CPC Class Codes: H01H 85/0241 Structural association of a fuse and another component or apparatus switches with built-in fuses H01H9/10, spark-gap arresters H01H85/44, transformers and inductances H01F27/402, capacitors H01G2/14, lamps H01K1/66, semiconductors H01L23/5256 or H01L23/62
• CPC Class Codes: H01H 85/046 Fuses formed as printed circuits
• CPC Class Codes: H01H 85/10 with constriction for localised fusing H01H85/11 takes precedence

Abstract

Some invention embodiments relate to a method for forming a fuse which electrically connects two metal surfaces (2) that are arranged on a printed circuit board (4) next to each other and spaced apart from each other. It is provided according to the invention that the two metal surfaces (2) are each partially covered with a protective coating (5), wherein a partial region forming a contact region (2a) remains uncovered, liquid soft solder material (1) which bridges the gap between the two metal surfaces (2) is applied onto the two uncovered partial regions (2a), and the protective coating (5) in a surrounding area of the solder material (1) is removed after the soft solder material (1) has solidified, in order to form receiving regions (2b) which are wetted by the solder material (1) when the latter fuses, with the result that the solder material (1) flows off from a printed circuit board region (3) between the two metal surfaces (2) and the electrical contact formed by the solder material (1) is interrupted. Furthermore, other invention embodiments relate to a printed circuit board with such a fuse.

Claims

1. A method for forming a fuse which electrically connects two metal surfaces that are arranged on a printed circuit board next to each other and spaced apart from each other, comprising the steps of:

partially covering the two metal surfaces with a protective coating, the protective coating is formed by solder mask, while a partial region forming a contact region remains uncovered,

applying liquid soft solder material onto the two uncovered partial regions to bridge the gap between the two metal surfaces and

after the soft solder material has solidified, removing the protective coating in a surrounding area of the solder material to form receiving regions which are wetted by the solder material when the latter fuses, with the result that solder material flows off from a printed circuit board region between the two metal surfaces and the electrical contact formed by the solder material is interrupted.

2. The method according to claim 1, wherein the protective coating is removed through the influence of radiation.

3. The method according to claim 1, wherein the protective coating is designed as a film and is removed by being pulled off.

4. The method according to claim 1, wherein flux is applied onto the two metal surfaces.

5. The method according to claim 1, wherein the protective coating is applied such that the protective coating surrounds the contact region.

6. The method according to claim 1, wherein the protective coating is applied such that the protective coating surrounds the contact region in the form of a bend.

7. A method for forming a fuse which electrically connects two metal surfaces that are arranged on a printed circuit board next to each other and spaced apart from each other, comprising the steps of:

partially covering the two metal surfaces with a solder-resistant protective coating, while a partial region forming a contact region remains uncovered, wherein the solder-resistant protective coating surrounds the contact region in a U or C shape,

after the partially covering, applying liquid soft solder material onto the two uncovered partial regions to bridge the gap on a surface of the printed circuit board between the two metal surfaces,

after the soft solder material has solidified, removing the solder-resistant protective coating in a surrounding area of the solder material to form receiving regions which are wetted by the solder material when the latter fuses, with the result that solder material flows off from a printed circuit board region between the two metal surfaces and the electrical contact formed by the solder material is interrupted.