Press-Formed Bulkhead Corner Flanges for Wrinkle Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods struggle to produce press-formed products with continuous flange parts from high-tensile strength steel plates for automobile structural members, as they often result in wrinkles, which hinder welding and stability, especially due to high yield stress and out-of-plane deformation.
Innovation Solution
A press-formed product design featuring a top plate with flange parts extending from its sides, connected via a corner flange part with a specific thickness distribution and curvature, formed using a production method and device that includes a punch, die, and convex-shaped tool to suppress wrinkles by promoting shear deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high-tensile strength steel plate is used for press-formed products, then strength and weight reduction are improved, but wrinkle formation increases due to high yield stress
Solution Approach 1:
The patent applies preliminary action by forming the corner flange part before the side flange parts during the press-forming process. This sequential forming approach allows the corner region to be pre-deformed into a convex shape, which prevents wrinkle formation when the side flange parts are subsequently formed. The preliminary formation of the corner flange part creates a favorable stress distribution that eliminates the wrinkle-prone conditions associated with high-tensile strength steel plates.
Solution Approach 2:
The patent changes the forming parameters by introducing a two-stage press-forming process with different pressing forces and sequences. The first stage forms the corner flange part with a specific convex shape, while the second stage forms the side flange parts. This parameter change in the forming process allows the high-tensile strength steel plate to be shaped without wrinkle formation, maintaining both strength and manufacturing precision.
2Strength
If continuous flange parts extending from corner parts are formed, then three-point bending crush performance is improved, but wrinkle formation increases due to out-of-plane deformation
Solution Approach 1:
The patent applies preliminary action by forming the corner flange part that extends from the corner parts before forming the side flange parts. This creates a continuous flange structure that enhances three-point bending crush performance while preventing wrinkles. The preliminary formation of the corner region establishes a convex shape that guides subsequent deformation and prevents out-of-plane wrinkling.
Solution Approach 2:
The patent segments the flange forming process into two distinct stages: first forming the corner flange part, then forming the side flange parts. This segmentation allows each region to be formed under optimized conditions, with the corner flange part receiving special attention to prevent wrinkles while achieving the continuous flange configuration needed for high crush performance.
3Ease of manufacture
If conventional press-forming method is used, then production simplicity is maintained, but wrinkle formation prevents continuous flange parts from being formed
Solution Approach 1:
The patent modifies the conventional press-forming method by introducing a preliminary forming step for the corner flange part. This additional step, while slightly increasing process complexity, enables the formation of continuous flange parts without wrinkles. The preliminary action creates a convex shape in the corner region that prevents subsequent wrinkle formation during side flange part formation.
Solution Approach 2:
The patent changes the press-forming parameters by implementing a two-stage forming process with different pressing forces, sequences, and tool configurations. The first stage forms the corner flange part with specific parameters, and the second stage forms the side flange parts. These parameter changes enable continuous flange formation while maintaining reasonable production simplicity.
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 solution enables the production of press-formed products with suppressed wrinkles, enhancing three-point bending crush performance and ensuring stable welding, thus improving the structural integrity of automobile components.
Implementation Method 1
folds the blank prior to the folding of the blank by the die, by relative movement of the convex-shaped tool to the punch, and thereby forms the corner flange part
Data Source
Figure 1~2A
Figure 2B~2D
Figure 3A
AI summary
A bulkhead (10), which is a press-formed product, includes a top plate part (11), side flange parts (14) and corner flange parts (15). The side flange parts (14) each extend from respective sides (12) of the top plate part (11). The corner flange parts (15) each extend from respective corner parts (13) of the top plate part (11). The corner flange part (15) connects the side flange parts (14) to each other. In the corner flange part (15), a part having a minimum value of plate thickness is present in a central portion in a circumferential direction, and parts having a maximum value of the plate thickness are present on both sides thereof. A ratio of the maximum value and the minimum value is in a range of more than 1.0 to 1.6 or less. In the press-formed product, wrinkles are suppressed in the corner flange parts, and the press-formed product is suitable for a reinforcing member for an automobile structural member.