Motor Vehicle Stamping Junction Setback to Drain Cataphoresis Liquid

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing motor vehicle body structures with horizontal common junctions between stampings tend to accumulate cataphoresis liquid after anti-corrosion treatment, leading to leakage and retention issues.

Innovation Solution

The design features a first stamping with a downward inclined edge and a second stamping with a horizontal joining edge, where the second stamping's edge is set back relative to the first's fold, and includes a cutout and projection configuration to reduce liquid accumulation and improve drainage, with specific dimensions and geometries to enhance welding efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If two stampings are joined with a horizontal common junction, then the structure is simple and easy to manufacture, but cataphoresis fluid accumulates at the junction

Engineering Contradiction:
Improvestructural simplicityVSAvoidfluid accumulation
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The invention transitions from a horizontal junction to a vertical junction configuration. The first stamping is positioned vertically relative to the second stamping, creating a vertical junction that utilizes gravity to prevent fluid accumulation. This dimensional change eliminates the horizontal surface where cataphoresis fluid would otherwise pool.

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

Solution Approach 2:

Instead of having the first stamping extend horizontally from the second stamping (conventional approach), the invention inverts the configuration by having the first stamping extend vertically downward. This inversion changes the orientation of the junction from horizontal to vertical, fundamentally altering fluid behavior at the joint.

Inventive Principle:
Principle #13The other way round (Inversion)

2Ease of manufacture

If the first stamping extends horizontally from the second stamping, then the assembly is straightforward, but fluid drainage is poor

Engineering Contradiction:
Improveassembly simplicityVSAvoidfluid drainage efficiency
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The invention changes the orientation of the first stamping from horizontal to vertical extension. This dimensional change creates a vertical drainage path that allows cataphoresis fluid to flow downward by gravity, significantly improving drainage efficiency compared to horizontal extension.

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

3Strength

If the joining edges are flush aligned, then the weld joint is strong, but cataphoresis fluid can penetrate into the joint

Engineering Contradiction:
Improveweld joint strengthVSAvoidfluid penetration
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The invention introduces asymmetric positioning where the joining edge of the first stamping is set back relative to the joining edge of the second stamping. This asymmetric configuration creates an offset that prevents fluid penetration while maintaining weld joint integrity through proper overlap and bonding.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The setback configuration creates a localized protective feature at the joining edge. The offset geometry specifically addresses the fluid penetration issue at the joint interface without compromising the overall structural strength, providing localized protection where needed.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3891049B1Arrangement of metal sheets to prevent cataphoresis liquid flowing into a flap opening gutter
Publication Date: 2024.03.13 STELLANTIS AUTO SAS
  • EP3891049B1 patent drawingFigure 1

AI summary

The invention relates to a motor vehicle body comprising: a first deep-drawn part (2) with a joining edge (6) and a vertical or downwardly-inclined portion (8) adjacent to the edge (6) via a portion (10) forming a fold; a second deep-drawn part (4) with a longitudinal joining edge (12), the edge (12) being horizontally superimposed on the joining edge (6) of the first deep-drawn part (2); remarkable in that the joining edge (12) of the second deep-drawn part (4) has a transverse rim (14) on the joining edge (6) of the first deep-drawn part (2), the rim (14) being set back with respect to the portion (10) forming a fold of the first deep-drawn part (2).