Rigid Cross Chassis Structure for Impact Force Distribution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing chassis structures for both thermal and electric motor vehicles face challenges in maintaining structural integrity and absorbing impact forces effectively, particularly when the battery and fuel tank are positioned between different crossmembers, leading to potential shearing and structural weaknesses, especially in vehicles of varying lengths or propulsion types.

Innovation Solution

A metal chassis structure featuring two longerons connected by crosspieces with a rigid metal cross, comprising two crossed rectilinear branches with four free ends, where two ends are fixed to one crosspiece and the other two to an adjacent crosspiece, allowing for improved force distribution and reduced shearing risks, and optionally incorporating a stiffening plate for added stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the same chassis structure is used for both thermal and electric vehicles with vacant spaces between crosspieces, then manufacturing cost and complexity are reduced, but structural integrity and impact resistance deteriorate due to shearing risks and weakness in vacant zones

Engineering Contradiction:
Improvechassis structure complexityVSAvoidstructural integrity
Core Design Contradiction:
Device complexityVSStrength

Solution Approach 1:

The rigid cross is segmented into two rectilinear branches that connect to adjacent crosspieces separately, allowing each branch to independently manage force transmission paths and distribute impact loads more effectively across the chassis structure

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The rigid cross introduces a new spatial dimension by connecting adjacent crosspieces through a perpendicular rigid structure, creating additional force distribution pathways in the transverse direction that prevent shearing in the longitudinal direction

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

2Strength

If a rigid cross connecting adjacent crosspieces is added to improve impact resistance, then structural integrity and force distribution are improved, but device complexity and manufacturing cost increase

Engineering Contradiction:
Improveimpact resistanceVSAvoidchassis structure complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The rigid cross is strategically positioned only at critical locations where adjacent crosspieces require enhanced connection for impact resistance, rather than uniformly across the entire chassis, allowing local reinforcement without global complexity increase

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The rigid cross combines two rectilinear branches made of rigid material (metal, polymer, or composite) to create a composite structural element that integrates multiple force transmission functions into a single component

Inventive Principle:
Principle #40Composite materials

Data Source

PatentEP3057852B1Chassis structure for a motor vehicle with a heat engine or an electric motor vehicle
Publication Date: 2018.06.27 RENAULT SA
  • EP3057852B1 patent drawingFigure 1~2
  • EP3057852B1 patent drawingFigure 3~4

AI summary

The invention relates to a chassis structure (10) of a motor vehicle (1) made of metal, including two side members (11, 12) connected by cross-members (14, 15), characterized in that said structure includes a rigid metal cross (20) connecting two adjacent cross-members (14, 15), said rigid cross comprising two crossed straight arms (21, 22) and four free ends, two of the free ends being rigidly attached to one (14) of said adjacent cross-members, the other two free ends (23c, 23d) being rigidly attached to the other (15) of said adjacent cross-members.