Vehicle Roof Structure With Deformable Coupling Section
Solution Overview
Problem
Existing vehicle roof structures face challenges in reducing vehicle weight while effectively absorbing collision loads during side collisions, as the roof reinforcement portion made of fiber-reinforced plastic tends to break if the collision load is not absorbed by other parts, leading to inadequate load absorption efficiency.
Innovation Solution
Incorporating a coupling section with a weak section that deforms under collision loads, featuring protruding and indented bead portions to distribute the load and pivot during deformation, allowing the roof reinforcement portion to absorb the load after initial deformation, thus maintaining structural integrity and load absorption efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If the roof reinforcement portion is made of fiber reinforced plastic to reduce weight, then weight reduction is achieved, but the roof reinforcement portion may break at an initial stage of side collision if collision load is not absorbed by other parts
Solution Approach 1:
The coupling section is divided into a first coupling member connected to the roof side rail and a second coupling member connected to the roof reinforcement portion. This segmentation allows the first coupling member to absorb collision loads through deformation before they reach the fiber reinforced plastic roof reinforcement portion, preventing premature breakage while maintaining weight reduction benefits.
Solution Approach 2:
The first coupling member acts as an intermediary element between the collision load source and the roof reinforcement portion. It absorbs and dissipates collision energy through its deformation characteristics, protecting the fiber reinforced plastic roof reinforcement portion from direct high-stress impact that would cause breakage.
2Weight of moving object
If the roof reinforcement portion is made of fiber reinforced plastic, then weight reduction is achieved, but the structural integrity during initial collision stages is compromised
Solution Approach 1:
The coupling section is divided into a first coupling member connected to the roof side rail and a second coupling member connected to the roof reinforcement portion. This segmentation allows the first coupling member to absorb collision loads through deformation before they reach the fiber reinforced plastic roof reinforcement portion, preventing premature breakage while maintaining weight reduction benefits.
Solution Approach 2:
The material properties and structural parameters of the coupling members are optimized to create a progressive deformation mechanism. The first coupling member is designed with parameters that allow it to deform preferentially under collision loads, changing the stress distribution parameters to protect the roof reinforcement portion while maintaining overall structural integrity.
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 vehicle roof structure effectively reduces vehicle weight while enhancing collision load absorption efficiency by allowing the weak section to deform first, thereby stabilizing the load transmission to the roof reinforcement portion, ensuring stable absorption and maintaining the coupled state during side collisions.
Implementation Method 1
The weak section deforms under a collision load in the vehicle width direction
Implementation Method 2
collision load in a side collision of the vehicle is absorbed by the weak section at an initial stage of the side collision
Implementation Method 3
The roof reinforcement portion is formed of fiber reinforced plastic, enabling a weight reduction in the roof section, and hence in the vehicle body, to be achieved
Implementation Method 4
In a side collision of the vehicle, a collision load transmitted through the center pillar and the roof side rails may be sustained by the roof reinforcement portion
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
The present disclosure provides a vehicle roof structure including: a left and right pair of roof side rails configuring part of a roof section of a vehicle body, the roof side rails are supported by a center pillar configuring part of the vehicle body and extend along a vehicle front-rear direction; a roof reinforcement portion formed of fiber reinforced plastic, the roof reinforcement portion disposed between the roof side rails so as to extend along a vehicle width direction; and a coupling section formed of metal, the coupling section couples the roof side rails and the roof reinforcement portion, and includes a weak section, the weak section deforms under a collision load in the vehicle width direction prior to the roof reinforcement portion undergoing bending deformation under the collision load.