Hemmed Panel Body Assembly With Hidden Butt-Joint Step
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional panel body manufacturing methods expose welding traces on the surface, making it difficult to achieve both good internal and external appearance quality.
Innovation Solution
The method involves pressing the first panel to form a single plane at the joined portion, arranging the main surface of the first panel on the second panel side, and hemming the second panel against the edge portion including a sloped portion, ensuring the joined portion is hidden inside the panel body.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the second panel is hemmed to sandwich the edge portion of the first panel including the step portion, then distortion in the second panel is prevented, but the joined portions (welding traces) are exposed on the surface of the panel body
Solution Approach 1:
The first panel is pressed in advance to form a sloped portion at the joined portion, creating a single plane on the front side. This preliminary action ensures that when the second panel is hemmed, the joined portion is positioned on the rear side rather than being exposed on the surface, thus preventing distortion while maintaining surface appearance quality
Solution Approach 2:
The pressing process creates a three-dimensional sloped portion that redirects the joined portion from the front surface to the rear side. By changing the spatial dimension and orientation of the joined portion through forming the sloped structure, the solution simultaneously achieves distortion prevention and surface appearance quality
2Manufacturing precision
If the step portion in the edge portion of the first panel is partially cut off, then distortion in the second panel is suppressed, but the manufacturing process becomes more complex
Solution Approach 1:
Instead of cutting off the step portion, the invention changes the geometric parameters of the first panel by pressing it to form a sloped portion. This parameter change (creating an inclined surface) achieves the same distortion suppression effect as cutting but through a different manufacturing approach that avoids additional cutting operations and complexity
3Weight of moving object
If two panel materials of different sheet thicknesses are butted and joined, then weight reduction is achieved, but the joined portions are exposed on the surface making it difficult to achieve good appearance quality
Solution Approach 1:
The first panel is pressed in advance to form a sloped portion that positions the joined portion on the rear side. This preliminary action ensures that the weight reduction benefit from using different sheet thicknesses is achieved while the joined portions remain hidden, maintaining surface appearance quality
Solution Approach 2:
The sloped portion creates a local structural feature that differentiates the front and rear sides of the first panel. The front side maintains a smooth single plane for appearance quality, while the rear side accommodates the joined portion, allowing local structural variation to solve the appearance problem
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
This approach achieves both good internal and external appearance quality by hiding the joined portion and suppressing distortion, enhancing durability and appearance of the panel body.
Implementation Method 1
the first panel is pressed so that the main surfaces of the two panel materials on the joining side form a single plane, a sloped portion due to the difference in sheet thickness appearing on the rear side
Implementation Method 2
the first panel and the second panel are joined by hemming the second panel against the edge portion of the first panel including the sloped portion
Data Source
AI summary
In the manufacture of a panel body composed of a first panel, which has a structure in which two panel materials of different sheet thicknesses are butted and joined, and a second panel, which is arranged on the outside of the first panel and connected thereto by hemming, the first panel is pressed so that the main surfaces of the two panel materials on the joined portion side form a single plane, and a sloped portion due to the difference in sheet thickness appears on the rear side thereof, the main surface of the first panel on the joined portion side is arranged on the second panel side, and hemming of the second panel is performed against the edge portion of the first panel that includes the sloped portion, thereby achieving good interior and exterior appearance quality of the panel body.