Forged Aluminum Motor Vehicle Door Intermediate Shell

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing motor vehicle door intermediate shells face challenges in achieving high strength and accident stability while minimizing weight and production effort, as increased wall thickness and additional reinforcements lead to high weight and costly production processes.

Innovation Solution

The intermediate shell is produced using solid forming, specifically forging, allowing for localized control of mechanical resilience and wall thickness, using light metal alloys like aluminum or magnesium alloys, and incorporating reinforcement and connection elements forged during the process to enhance strength and reduce weight.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the wall thickness is increased throughout the entire intermediate shell or additional reinforcement components are added to meet strength requirements, then the strength and accident stability are improved, but the weight of the intermediate shell and the entire door increases significantly

Engineering Contradiction:
ImprovestrengthVSAvoidweight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The patent applies local quality by varying the wall thickness of the intermediate shell according to the specific load requirements of different regions. Areas subject to higher mechanical stresses are formed with greater wall thickness, while areas with lower stress requirements use thinner walls. This localized adaptation allows the shell to achieve the necessary strength and accident stability without uniformly increasing weight throughout the entire structure.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent utilizes parameter changes by adjusting the wall thickness parameter discontinuously and locally across different regions of the intermediate shell. This enables optimization of the strength-to-weight ratio by matching the structural parameters to the actual stress distribution, thereby achieving high strength requirements while minimizing overall weight.

Inventive Principle:
Principle #35Parameter changes

2Strength

If additional reinforcement parts are added to meet strength requirements, then the strength is improved, but the production complexity and joining operations increase, resulting in higher costs

Engineering Contradiction:
ImprovestrengthVSAvoidproduction complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent merges the reinforcement function directly into the intermediate shell structure itself, eliminating the need for separate reinforcement components. By integrating the load-bearing function into the shell's own geometry through localized wall thickness variations, the design reduces the number of parts and joining operations required, thereby simplifying production and reducing costs while maintaining the necessary strength.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The intermediate shell is designed to perform multiple functions: it serves as both the structural framework and the load-bearing element simultaneously. By making the shell itself multi-functional, the patent eliminates the need for dedicated reinforcement parts, reducing production complexity and joining operations while achieving the required strength and accident stability.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Ease of manufacture

If cast or sheet metal components are used for the intermediate shell, then production is simplified, but extensive reworking is necessary and mechanical resilience is lower compared to massively formed parts

Engineering Contradiction:
Improveease of productionVSAvoidmechanical resilience
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent changes the manufacturing parameter from casting or sheet metal forming to massive forming (forging). This parameter change fundamentally improves the mechanical resilience by creating a homogeneous, compacted fiber flow structure throughout the material, eliminating the weaknesses inherent in cast voids or sheet metal joints while maintaining production efficiency.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs the principles of composite material structure by creating a homogeneous, finely distributed grain structure through massive forming. This results in a material composition with superior mechanical properties, combining the ease of production with enhanced mechanical resilience and accident stability.

Inventive Principle:
Principle #40Composite materials

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

This approach results in a lightweight, high-strength intermediate shell with reduced production effort and costs, improved tensile strength, and enhanced accident performance, while avoiding the drawbacks of cast and sheet metal constructions.

Implementation Method 1

it is produced at least in regions from a light metal blank by solid forming, preferably by forging

Methodology Applied
Scientific EffectSolid forming: Deformation

Implementation Method 2

produced at least in regions from a light metal blank by solid forming, preferably by forging

Methodology Applied
Scientific EffectForging: Deformation

Implementation Method 3

during massive forming, in particular during forging, a fiber flow in the component can be suitably designed or influenced. In particular, it is possible to collect fibers in certain areas

Methodology Applied
Scientific EffectFiber flow: Deformation

Data Source

PatentEP2948327B1Intermediate shell for a motor vehicle door, method for producing an intermediate shell, and a door for a motor vehicle
Publication Date: 2020.04.29 MERCEDES BENZ GROUP AG
  • EP2948327B1 patent drawingFigure 1

AI summary

An intermediate shell for a motor vehicle door, in particular a side door of a motor vehicle, is disclosed. The intermediate shell is produced at least in regions from a light metal blank by massive forming, preferably by forging.