Press-Formed Structural Member With Protrusions for Bending Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing structural members for automobiles, such as side sills, require enhanced collision safety performance and higher strength characteristics in three-point bending tests, while also needing greater design flexibility and reduced lengthwise shock absorption components to accommodate limited spaces.
Innovation Solution
A press-formed article with a specific structure, including a top sheet portion, standing wall portions, protrusion portions, and flange portions, is designed to achieve high strength and improved collision safety performance. The article is manufactured using a method that involves hot stamping or hot press forming, allowing for the formation of a martensite structure with high tensile strength and Vickers hardness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional structural members are used to ensure basic collision safety, then manufacturing simplicity is maintained, but collision safety performance and strength characteristics are insufficient
Solution Approach 1:
The structural member is divided into multiple wall portions (first, second, third, fourth wall portions) with different configurations. Some wall portions have protruding parts while others have recessed parts, creating segmented functional zones that collectively improve collision safety and strength characteristics without compromising manufacturing simplicity.
Solution Approach 2:
Different wall portions are designed with locally optimized structures: certain wall portions have protruding parts to enhance strength in specific regions, while other wall portions have recessed parts for weight reduction or design flexibility. This local differentiation allows the member to achieve high overall strength characteristics while maintaining manufacturing efficiency.
2Reliability
If shock absorbing members are provided over the entire length to improve collision safety, then collision safety performance is enhanced, but design flexibility is reduced and space requirements increase
Solution Approach 1:
The shock absorption function is segmented and distributed across specific wall portions rather than providing continuous shock absorption along the entire length. The first, second, third, and fourth wall portions each contribute to collision safety through their specific configurations, allowing the member to achieve high collision safety performance while maintaining design flexibility and accommodating limited spaces.
Solution Approach 2:
Instead of providing shock absorption over the entire length (excessive action), the invention applies shock absorption features selectively to specific wall portions (partial action). This partial implementation is sufficient to achieve the required collision safety performance while preserving design flexibility and reducing space requirements.
3Adaptability or versatility
If multiple processing steps are used to form complex structures, then design freedom is increased, but manufacturing complexity and difficulty increase
Solution Approach 1:
The formation of protruding parts and recessed parts in different wall portions is merged into a single press-molding process. The press-molding step simultaneously creates the complex geometry with multiple wall portions having different configurations, achieving high design freedom while maintaining manufacturing simplicity and avoiding multiple processing steps.
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 resulting formed article exhibits high strength, excellent characteristics in three-point bending tests, and a high degree of design freedom, while also being easily manufacturable. This solution enhances collision safety performance and allows for more flexible design applications in automotive structural members.
Implementation Method 1
The article is manufactured using a method that involves hot stamping or hot press forming, allowing for the formation of a martensite structure with high tensile strength and Vickers hardness
Data Source
Figure 1
Figure 2A~2B
Figure 3~4A
AI summary
A long formed article made of one steel sheet includes a top sheet portion extending in a longitudinal direction, a standing wall portion extending downward from each of both edges of the top sheet portion in a width direction, and a protrusion portion formed in a portion of the top sheet portion in the longitudinal direction by overlapping a portion extending toward an outside from each of both ends of the top sheet portion in the width direction and a portion extending toward the outside from an upper end of the standing wall portion, in a non-protrusion region, a recessed part extending in the longitudinal direction is formed in the top sheet portion, and a total value α of inner surface peripheral lengths of the top sheet portion and the standing wall portion in a cross section of the formed article perpendicular to the longitudinal direction in a protrusion region and a total value β of inner surface peripheral lengths of the top sheet portion, the standing wall portion, and the recessed part in the cross section of the formed article perpendicular to the longitudinal direction in the non-protrusion region satisfy 1.01 ≤ β/α ≤ 1.50.