Braze Depot Recess Geometry for Captive Solder in Metal Sheets

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for attaching solder to metal sheets in components like stamped and contact parts are prone to loosening during transport or vibration, leading to processing issues.

Innovation Solution

A method involving deep drawing to create an undercut recess in the metal sheet, allowing for secure attachment of solder deposits through a dovetail-shaped depression that captures the solder, preventing loss and ensuring a stable connection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If solder is applied to stamped and contact components in solder pads, then electrical connection is established, but the solder plates become loose or fall off during transport or vibration

Engineering Contradiction:
Improvesolder attachment reliabilityVSAvoidsolder plate stability
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The solder pad is segmented into a recess portion and a collar portion, creating distinct functional zones. The recess provides mechanical interlocking for the solder, while the collar provides additional support and containment, preventing the solder from becoming loose during transport or vibration.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The solder is nested within the recess formed in the solder pad, creating a captive structure. The collar surrounds the recess opening, providing an additional containment layer that secures the solder in place and prevents it from falling off during handling and transport.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Reliability

If a recess is created in the metal sheet to secure solder, then solder attachment reliability improves, but the opening section of the recess may be too large causing solder to become loose

Engineering Contradiction:
Improvesolder attachment reliabilityVSAvoidrecess opening area
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The recess is designed with an asymmetric cross-sectional profile, being larger at the bottom and smaller at the opening. This asymmetric geometry creates a mechanical interference fit that captures the solder while minimizing the opening area, preventing solder from becoming loose during transport.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The solution extends from a two-dimensional flat solder pad to a three-dimensional structure with depth. By creating a recess with controlled opening area and adding a collar, the design utilizes the third dimension to secure the solder mechanically, reducing the problematic opening area while maintaining attachment reliability.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The method securely attaches solder deposits to metal sheets, preventing loss during handling and enabling reliable further processing by creating a captive, form-fitting solder depot with improved solder connection quality.

Implementation Method 1

The recess is created by tensile-compressive forming, in which a portion of the material is displaced from the top side toward the bottom side using non-cutting forming, so that the displaced material protrudes from the bottom side.

Methodology Applied
Scientific EffectTensile-compressive forming: Deformation

Implementation Method 2

The material protruding from the underside due to deep drawing is pressed in the opposite direction, i.e., pressed toward the top. During this time, a punch is located in the recess, so that the recess can no longer be completely filled. Instead, the pressed material should flow laterally past the punch. This creates a collar that surrounds the punch and the recess containing the punch.

Methodology Applied
Scientific EffectPressing: Compression

Implementation Method 3

The collar is then at least partially pressed towards the recess. This reduces the cross-sectional area of ​​one opening of the recess. An undercut recess is created.

Methodology Applied
Scientific EffectMaterial displacement: Deformation

Data Source

PatentEP4076817B1Method of manfacturing a braze depot and corresponding metal sheet with a braze depot, such that the opening section of the recess is reduced
Publication Date: 2024.03.27 KME GERMANY GMBH & CO KG
  • EP4076817B1 patent drawingFigure 1~2
  • EP4076817B1 patent drawingFigure 3~4
  • EP4076817B1 patent drawingFigure 5~6

AI summary

The invention relates to a method for producing a solder deposit in a metal sheet (1), comprising the following steps: a) a metal sheet (1) has an upper side (2) and an underside (3), wherein, in a first step, a depression (6) is introduced into the upper side (2) by means of deep drawing; b) then a collar that protrudes in relation to the upper side (2) is formed on the on the depression (6) by shaping the material of the metal sheet (1); c) and then the collar is pressed at least partially in the direction of the depression (6) so that a cross-sectional area of an opening of the depression (6) is reduced.