Vehicle Subframe with Deflected Side Members and Cross Member Coupling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing vehicle subframes fail to prevent unnecessary deformation in side members during crashes, leading to inadequate crash performance in frontal collisions.

Innovation Solution

A vehicle subframe design featuring side members with deflected portions and cross members that distribute crash loads, preventing outward deformation and ensuring required crash performance by coupling side members with enlarged joint portions and strategically placed attachment members.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If side members are coupled by a single cross member with a middle vehicle-body attachment portion, then productivity of attachment is improved, but unnecessary deformation occurs in the side members during crash

Engineering Contradiction:

Improveattachment productivityVSAvoidcrash performance

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The subframe is divided into multiple cross members (first cross member and second cross member) that are positioned at different locations along the side members. This segmentation allows the structure to better distribute and manage crash loads, preventing unnecessary deformation in the side members while maintaining attachment productivity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces a spatial arrangement where cross members are positioned at different longitudinal locations along the side members, creating a three-dimensional load distribution network. This dimensional approach allows crash loads to be distributed across multiple attachment points rather than concentrated at a single middle portion, improving crash performance without sacrificing productivity.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Weight of moving object

If thin plates are used in the middle portion of side members, then weight is reduced, but deformation occurs in the fragile portion during crash

Engineering Contradiction:

Improvesubframe weightVSAvoidcrash resistance

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The patent applies different plate thicknesses at different locations of the side members. Thin plates are used in the middle portions to reduce weight, while thicker plates or reinforced structures are used at the front and rear portions where crash loads are concentrated. This local quality differentiation maintains overall weight reduction while ensuring sufficient strength and crash resistance at critical locations.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The structural design anticipates crash loads by positioning cross members at strategic locations before the crash force reaches the thin middle portions of the side members. This beforehand cushioning effect allows the thicker end portions and cross member attachments to absorb and distribute crash energy, protecting the thinner middle sections from excessive deformation.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Loss of energy

If front-rear direction members are bent in the middle portion to couple ends, then energy absorption in vehicle-width direction is improved, but unnecessary outward deformation occurs in offset crash

Engineering Contradiction:

Improvecrash energy absorptionVSAvoidside member deformation

Core Design Contradiction:

Loss of energyVSShape

Solution Approach 1:

The coupling function is segmented between the bent middle portions of the side members and the separately positioned cross members. The bent portions provide energy absorption through controlled deformation, while the cross members positioned at multiple locations prevent excessive outward deformation by providing additional structural support and load distribution paths during offset crashes.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS11702141B2Subframe for vehicle

Publication Date: 2023.07.18 F TECH INC

AI summary

In a vehicle subframe 1, a first side member has a first extending portion that extends while being deflected outward on one side in a width direction as approaching from a rear side to a front side, a second side member has a second extending portion that extends while being deflected outward on the other side in the width direction as approaching from the rear side to the front side, and a second cross member is further included which is opposed to the first cross member on the front side thereof and couples a portion of the first extending portion in which the degree of outward deflection on the one side in the width direction becomes large and a portion of the second extending portion in which the degree of outward deflection on the other side in the width direction becomes large to each other.